- Welcome, everyone,

I'm Chris Cirmo,

the Dean of the College of

Letters and Science at UWSP.

I want to welcome you to a

community lecture series tonight

highlighting our faculty

scholarship and its relation

to our community.

Tonight's lecture

is being recorded by

Wisconsin Public Television,

for broadcast as part of its

University Place series.

First of all, I'd like to

thank a couple of folks here

at the Portage County Library:

Bob Stack, the director,

and Scott Tappa, who's my

assistant for Marketing,

Public Relations and Events.

Tonight's lecture is entitled

Aquaponics: Sustainable

Food Production.

And our presenter

is Chris Hartleb,

who is professor of biology

at UWSP, and director of

the Northern Aquaculture

Demonstration Facility

in Bayfield, Wisconsin.

He's also Research

Director of the new

Aquaponics Innovation Center

in Montello, Wisconsin.

The Aquaponics Innovation

Center is a really neat story.

Chris assisted us in getting

about a $700,000 grant

from the Wisconsin Economic

Incentive Grant Program

last year, and worked

with a private firm

by the name of Nelson & Pade.

And Rebecca Nelson and

John Pade were pivotal

private partners in

this partnership,

and I think Chris is

going to talk a little bit

about that tonight.

I've worked with

Chris for six years.

I've been here

six years as dean,

and I'm going on my

seventh year now.

And I can say unequivocally

that Chris is one of the more

energetic, creative

and imaginative

people I've ever met.

We've gotten to know each

other on five-hour drives

up to Bayfield, Wisconsin

and an hour and a half drives

down to Montello and

always have something great

to talk about.

Chris has done wonders

with our Northern Aquaculture

Demonstration facility

in Bayfield, and the

work that he's done

as a faculty member

and as an entrepreneur

is nothing short of magnificent.

I just want to commend Chris

for his incredible drive

and entrepreneurship.

Chris received a Bachelor's

Degree in Biology

from Rensselaer Polytechnic

Institute in Troy, New York.

His M.S. in Limnology from the

University of New Hampshire

and his PhD in

Fisheries Ecology from--

excuse me here--

his PhD in Fisheries Ecology

from the University of Maine.

He's been a professor of

Biology at UWSP for 19 years,

where he's had experience

working with larval fish,

cool and cold water aquaculture,

and most recently, aquaponics,

which he's going to

talk about tonight.

He teaches courses in

aquaculture, aquaponics,

fisheries ecology

and field ecology.

It's my pleasure to

welcome Dr. Chris Hartleb

as tonight's special guest,

speaking about Aquaponics:

Sustainable Food Production .

Chris?

(audience applause)

- Well, thank you, and thank

you for joining me tonight.

As Chris just mentioned, I

want to speak about the topic

of aquaponics, which we'll

discuss in some more detail,

some of the specifics about it.

But the other part is, is

talk about it as a sustainable

food production system.

And before we can get into

that, I think what we have

to look at really is

how does it compare

with our more traditional

types of agriculture,

how much they're producing

and what their impact is

and then try to see where

aquaponics can fit into

food production.

So if you think about

traditional agriculture,

you know, most of the time,

you're thinking about corn

and soybeans or

potatoes in a field.

You're thinking about

cows, pigs or chickens.

Something to keep in mind is,

is are we producing enough?

And if not, what are

we willing to sacrifice

to raise production of these

different plants and animals?

I kind of got this

graph together here

from the U.S. Department

of Agriculture,

and what you can see is,

is that except for Asia,

traditional agriculture has

really kind of maxed out

in most other continents

and most other locations.

So in essence, we're either

producing most of the food

that we can, or we've

reached a limit on how much

we're willing to produce.

As you can see in

this graph, basically,

the world population as we

know continues to increase.

Most people look at

the top line here

of world agriculture production

and say to themselves,

"Well, it looks like we're

actually keeping ahead

"of the pace of human

population growth."

But the fact is, that most of

that increase in production

is actually happening

over in Asia,

where all the other continents

have basically gone flat.

So how long can Asia

continue to produce

more and more

agricultural products

to feed the growing population?

I think most experts would say

that we're coming very

close to the limit

that we can actually produce.

So how are we going to

feed the world?

And as we feed the world,

what are we willing

to sacrifice?

Are we willing to pollute

the environment even more?

You know, adding fertilizers?

Adding different types of

biocides to these crops

just so we can

produce more and more?

Are we willing to damage

habitats and wildlife?

Because we've got to

clear more and more land

in order to put these

crops and plant them.

And of course, as you

look at these animals,

what they're doing with

a lot of animals is,

is that they're stocking

them at higher densities,

crowding them together.

This often results

in the spread,

a rapid spread of diseases,

so they're adding more

and more antibiotics,

pesticides, herbicides,

you know, to these crops

to keep them healthy.

But in the end, we're the

ones consuming those crops.

So how are we going to

meet this worldwide demand

for agricultural products

without accepting

these side effects being

applied to what we eat?

Well, all you have to think

about is, is what could go wrong

with this system?

Can we stay on that same path?

So if you've been paying

any attention to the news

over the past few months,

and in fact, the CDC released

an update this morning,

there have been three deaths

and 558 people sick from

that vicious little creature

known as the cucumber.

And this morning,

they actually said that,

that number of sick has passed

over 600 people already.

Why is this happening?

For the most part, it's

salmonella poisoning

that's occurring because these

crops are being fertilized

with different types of manures,

and then these crops are

getting these diseases on them,

and then they're going off to

market and we consume them.

So what about food safety?

You know, is there anybody

out there who's keeping an eye

on the food that

we're actually eating?

Most people would say,

okay, and yet this harmless

little cucumber has now

made that many people sick,

and is responsible for at least

three deaths at this point.

What about our resources?

Water resources to start.

Again, if you haven't

been paying any attention

to the news you might

have missed this,

but most of the Western U.S.,

specifically California,

is in the midst of

a massive drought.

In fact, they refer to it as

a four-year record drought.

And they've instituted

massive changes out there

and fines if you use

too much water.

I found this photograph

here just to be remarkable

in that this is an

agricultural field.

There's a tractor.

They really don't

have that much ground

that they have to care

for with that tractor.

That's the only area that's

getting water at this moment.

So we've got these droughts

that are coming out.

What's it going to do to

the agricultural crops?

Well, they're going to lower

the amount they can harvest.

They're going to

increase the prices,

and then we're going to have

to come up with some other

ways to grow these crops

to feed the people.

And then it comes back to the

statement of sustainability.

And that is, is how long

are we willing to put up with

all of this?

Or maybe the other

way to look at it is,

how much longer can the

Earth put up with it?

And if you look at this as

the world's population booms,

will its resources

be enough for us?

Well, these are mostly the

predictions that are coming out

of reports, this one

from National Geographic.

If you look at that,

it basically says

the human population

is increasing.

We've said that already.

And with that, our agricultural

output has to increase

to match it as well.

But most experts say that

we're not going to be able

to sustain that type of

output, because the resources

are going down, and the

pollution is going up.

So what's going to

happen over time is,

is that the amount

of food produced is suddenly

going to crash.

And likewise, you're

going to get more and more

starving people, so then

your human population

is going to start to

crash as well.

So we really have to take

a global view of all this,

and start examining it to say

maybe traditional agriculture

is not for the long term.

Maybe we need to

start supplementing it

with alternatives that

are out there.

And the alternative

obviously that I'm here

to talk to you about

tonight is the alternative

of aquaponics.

So what is aquaponics?

I've actually heard

people give me a variety

of definitions to it, but I

stick with this kind of more,

a basic form, and that is,

is that it's an integrated

production system

where you're raising

both plant and fish crops,

but it's in a completely

soilless environment

such that you get the

benefits of the fish

essentially feeding those crops,

and those crops returning

fresh water back to the fish.

There are some others

out there that,

they still include

certain types of soils

in their aquaponics, or they

enhance it with an addition

of different types of

nutrients or fertilizers.

I'd argue that, that's

not truly aquaponics

because it's a

hybrid version it.

Aquaponics says you're

doing it all in water.

What do we know

about aquaponics?

Well, I'm going to

show you today that,

I think it's a sustainable

production mechanism.

And that is that you

will be able to see this

closed circuit of

nutrients, water, and energy

just revolving around

growing both of these crops.

It's also a natural

production system.

It's fish producing fertilizer

that's feeding the plants,

returning fresh water

to the fish.

There's nothing artificial

being dumped into the system.

It's highly efficient

because it's what we refer to

as a closed loop

agriculture system,

Which means that things

don't enter and exit

throughout the production.

In this case, the water is

just recycled round and round

between the different

organisms so that you get

production.

Therefore, it's a conservative

use of water, space,

time, and labor.

Also, you can't apply

any of those biocides,

pesticides, herbicides,

insecticides to it.

Most of those are

used on the plants,

but almost every one of

them is toxic to the fish.

So if you did come across

a disease outbreak,

if you did have pests that

are in there and you apply it,

within hours, you'll actually

watch all the fish die,

and there shuts off the

nutrients going to the plants.

So you actually

cannot apply these

to the plants in the system,

and some people will say,

well what about the fish?

Do you give them antibiotics?

Do you treat them for disease?

Turns out, almost all of the

medicines available for fish

are toxic for plants.

So it really cuts you off

there that you can't add

all these different

biocides to the system.

As I mentioned before, it

produces both a protein crop

in the form of fish, as

well as a vegetable crop.

So you're practically raising

an entire meal.

If we can sort of tie into

that and try to figure out

how we can grow a dessert,

then we'd really have a nice,

three-course meal

for the night.

And then the last part of

which I want to talk about

a little later in

this presentation

is the fact that aquaponics

has the potential

to produce crops 365

days of the year.

It's done so, if the

aquaponics is done

in a controlled environment,

such as a greenhouse.

Around here, I think

most of us would agree,

that we'd be in favor of that.

I've walked into an

aquaponics greenhouse

in the middle of January

and seen about an eighth

of an acre of corn growing.

Now you might say to

yourselves, well it's corn,

we get a lot of

that in the summer.

Yeah, but think about what a

fresh ear of corn tastes like

in the middle of January.

And you could have

that right next door.

So it does have some unique

aspects that tends to attract

a lot of people to it as well.

Now that's not to say

you can't do aquaponics

without a greenhouse.

I've seen people do it in

their garage, their basement.

Nowadays, they're trying

to do it in warehouses.

On top of buildings.

And then if you, the

further south you head,

say the tropics, they do

away with the greenhouse

all together, because

they don't have a need to.

It's summer 12

months of the year.

Now one aspect of this,

as I frequently get

asked by people,

well, aquaponics sounds

new, sounds risky.

It's not something

I want to get into.

I'm going to wait and

see, you know those people

who get into it,

do they fall apart?

The fact is, is that

aquaponics is not new.

There is evidence, documentation

that over 1300 years ago,

the Aztecs actually had what's

referred to as chinampas,

and you can see them right

here in this diagram.

They're actually floating

rafts that they would push out

into lakes.

And in those rafts, they

would have plants growing.

And that was basically an

early form of aquaponics.

Water, where obviously

there are fish in the lake

that are producing nutrients,

and plants on these floating

rafts that would absorb

the nutrients and grow.

If you actually go back

about 1500 years ago,

the Chinese used an integrated

system of rice paddy fields

and fish.

In fact, this photo here

is actually a recent photo

because they're still doing it.

They haven't given up on it.

They raise the fish right

in the rice paddy field,

and they harvest the rice,

and the fish provide them

with the nutrients.

So aquaponics has been done

for a very long period of time.

It's just nowadays becoming,

I guess you could say,

technologically advanced.

And that's why I add the term

here "modern aquaponics."

Modern aquaponics is

where we start to add

technology into it.

Get computers involved in

controlling the green house.

Using different types of

technology to make the fish

more efficient at feeding and

the plants growing faster.

And I put up three different

bullet points here.

One of them I wanted to start

off with was Leonard Pampel.

He actually worked at the

Milwaukee Public Museum

in the 1960s and 1970s,

and he actually got three

patents when he was there.

And each one of them was

basically based upon,

at the museum, looking at fish

displays that they had there

that the fish tanks

would turn very green.

So what he did is,

behind the scenes,

the place where most of us

don't actually get to see

at the museum, he started

irrigating some of these plants

that he had in the back or

the back scenes of the museum,

and the plants would essentially

neutralize the water,

they would absorb the nutrients

and return clear water

back to the fish display

that people were looking at.

I just happen to mention it

because just three weeks ago,

I got a phone call from

a Mr. Leonard Pampel

who lives in northern

Wisconsin at the age of 96

and said, can I come

see the University's

new Aquaponics

Innovation Center?

And I said, how do I

have to get you there?

Do I have to come

and pick you up?

Can you make it?

He says, my neighbor

will drive me there.

And there he is, and

he came and looked

at the Aquaponics

Innovation Center,

spent a half day with

us when we were there.

He loved what he saw.

He loved to see where

we're taking aquaponics.

And he basically just said,

stop by, call me anytime.

I'd like to see

this program grow.

And he says, I have a lot

more good ideas, he says,

that I didn't share

with the Public Museum

even after I retired, he says,

that I could share with you.

And, you know, it's really

unique that you get to meet

one of the fore-founders of

an actual new modern industry

such as that.

He's not alone.

In the 1970s, there

was a facility known as

the New Alchemy Institute

at North Carolina State.

And they actually

started publishing

some of the more recent

science articles on what fish

and plants could be grown

in aquaponics.

And then the University of the

Virgin Islands in the 1980s,

a man by the name

of Dr. Jim Rakocy,

he did something that kind

of took it a step further

and that was that he

started applying economics

to aquaponics and said,

you know, you can talk

all you want about

sustainable food production,

but if it's not economical,

people are not going to do it.

So he started doing the math.

And what he found

is that essentially,

if you treat aquaponics as a

local food production system,

it's quite affordable and can

compete with anything else

that you can buy

in the supermarket.

He said, it's when you

add distance into it,

that aquaponics suffers

a little bit because now

you're getting into

transporting these products.

And you really can't beat

the current transportation

system for most of the goods

that we eat.

So that kind of gives you

a summary of the history

of aquaponics.

We're in the next

generation now,

the modern aquaponic world,

and we have to start addressing

some of the questions

or challenges that are out there

and I'll get to those a

little later in the lecture.

Go back to the

topic of sustainability

and that is, in order

for us to actually look

at aquaponics as a

sustainable food program,

we have to know what

its sustainability is.

Again, what we can do is

compare it to traditional

agriculture.

As I mentioned already,

it's a natural system

that results in the

recycling of nutrients.

So that helps us go a long way.

But the other is, is if we

compare it for some other

production systems, we

can see, how about beef?

It's pretty odd.

I put this presentation

together a little while ago

and yet this morning, on CNN,

they had a topic that said,

"Is beef the next SUV?"

I don't know if anybody read

that article, it was out there.

It caught my eye more

along the lines of,

what are they talking about?

Comparing a car to a cow.

The whole article

was about the fact

that beef production

worldwide is in a decline.

And the reason is, is that

it takes a lot of energy

and resources to raise a cow.

And in the end, it's

not very sustainable.

I just used one factor

here, and that is water

because that's what's

used in aquaponics,

and beef basically requires

between 5,000 to 20,000 liters

of water to raise one

kilogram of beef.

That's not really good.

That's not an

efficient use of water.

But I wanted to be fair

here as well, and that is,

is if you look at

extensive aquaculture,

now aquaculture is fish farming,

and extensive aquaculture

is that fish farming

which is done outdoors,

say, in ponds.

And what you can see is, is

that it's not too much better

when it comes to the water use.

You still need between 2500 to

over 375,000 liters of water

to raise a kilogram of fish.

So aquaculture in itself

is not the most perfect

sustainable system when it

comes to food production,

or I should say

extensive aquaculture.

But when you move things indoors

into a circulating system

such as aquaponics, suddenly

you don't have nature

playing a role in the process.

You're controlling nature.

And it turns out

that in aquaponics,

you need about 100

liters of water to raise

a kilogram of fish, because

that water is constantly

recycled through the system.

So at least from a

water perspective,

aquaponics appears to

be on the higher end

of sustainability,

especially, you know,

for water resources,

but in terms of food

production as well.

Now the other question, and

this one's rather interesting,

is that people say, well

where does aquaponics fit

in the grand scheme?

You know, what is its roots?

And I would argue that

it's probably a subset

of aquaculture.

And I find this really

interesting just because

this past summer, I was on

actually a federal review panel

where they were trying to

set up federal programs

in aquaponics, and this was

actually the first question

they asked.

Where does it fit?

Does it fit into

traditional agriculture?

Does it fit into aquaculture?

Does it fit into hydroponics?

And they really didn't

know where to put it.

Again, I was on the panel,

and I kind of argued with them

and said, I think it's a

sub-set of aquaculture.

Aquaculture is the science

and industry of raising fish.

And you're doing

that in aquaponics.

The other is, is that you do it

under controlled conditions.

Now I already mentioned

extensive to intensive ponds

flow through recycled systems.

Aquaponics, to me, seems

to be a recycled system.

It's recycling the water.

And you get the benefits

from aquaculture from it,

and that is, is that raising

fish is the most efficient

production of protein.

I have this little

name over here of FCR,

which stands for Food

Conversion Ratio.

It's a very simple equation.

How many pounds of food do

I have to feed my animal

to get a pound of growth?

And for most fish

production and aquaculture,

it ranges between one to two.

In other words, you can

feed fish one pound of food

and get one pound of

growth out of those fish.

You can't do much

better than that.

But some fish are a

little sloppy eaters,

and it may raise up to two.

If you do compare

that with things,

the closest is chickens

where it's about 2.5 pounds

of food to a pound of growth.

Then come pigs at

about 30 to one.

And then once again, our beef

comes along with the cows,

and they're like 100 to one.

So fish are a very

efficient user of the food

we're giving them.

They turn it into body growth,

and that's actually the

protein that you eat.

And again, it's a

conservative use of resources,

it's sustainable and consistent,

and aquaculture worldwide

is on a rapid incline

so that essentially, it's

becoming a very profitable

business for a lot of people.

So it seems that it

fits that model.

Now if that's true,

then we have to look at

a couple of questions.

And that is, again, I go

around and I ask people

and I say, do you eat seafood?

And they say, sure

I eat seafood.

And I say, well, where does

your seafood come from?

And where do you think

the general answer is

that people give you?

Supermarket, restaurant,

and then I say, well, where

does it come from before that?

And almost everybody will

say, it comes from the wild.

It comes from nature.

Well, the fact is, is less

and less is coming from nature

every year.

If you look at this

graph that's up here

and it shows you the

years across the top,

it shows you our stocks

of wild fish in the world.

Oceans, great Lakes and

what's happening to them.

And the fact is, is that all

of our fish that are out there

in the wild are already

fully exploited.

We're catching as much of them

as they are available to us.

In fact, many of them

are over-exploited

and quite a number of them,

32% of our fish stocks,

have completely collapsed.

So even though people think

their food comes from the wild,

more and more, or I should

say less and less of it

is actually coming from the wild

because there just aren't

any other fish out there

anymore.

So if that's the case,

then where are the fish,

the seafood that we eat, where

is it going to come from?

Well, I can tell you where

it's going to come from,

it's going to come

from fish farms.

Or farms such as

aquaponics growers.

Now here's some staggering

statistics about that seafood

that you're consuming.

And that is, did you know

that fish and fish products

or seafood contribute to

the largest food commodity

that are traded

internationally.

That's more than chickens,

cows, pigs, fruits,

and vegetables.

The U.S., though, imports

90% of its seafood.

So now you know.

It's not generally coming

from the wild anymore,

but this other thing is,

is that it's not coming

from the United States either.

Most of it's coming

from foreign countries.

But in those foreign

countries, about half of it

is farm-raised seafood.

So next time you go

to the supermarket

and you look at

the display case,

if they don't have signs

that say "Product of"

and list a country,

ask the grocer.

And if they have

that information,

which they actually do have,

they may just not be

sharing it with you,

but if they have that

information, then

they'll tell you,

well, that's from this

country, and this country.

Then say to them, well is

it farm raised or wild?

And then you'll know if you

have a really good grocer

because they should know

the answer to that question.

And then they can tell you, and

I think what you'll find is,

is 50% of what's in that display

case is coming from a farm.

Unfortunately, it's a foreign

farm, not a U.S. farm.

What impact does this

have on our economy?

As I said, it's the single

largest food commodity

that's traded.

This graph over here

basically shows you,

the blue arrows are

the imports of seafood,

whereas the green ones

are what we export.

And the disappointing thing

are the light blue arrows

down here which you can

see in the negative,

which means that we import

more than we export.

And you might say, well

what does that add up to

economically?

It adds up to about $10.4

billion dollars a year

in a seafood deficit.

So it's costing

us a lot of money

to bring in that seafood.

And the part that I

usually put up here, which,

if the financial aspect doesn't

kind of get you confused

or upset, this other one

usually gets me pretty upset,

and that is, is all that

foreign import of seafood

comes into this country,

but the FDA, the Food

and Drug Administration,

can only monitor as much

as they have resources

and labor that can monitor it,

and they're publicly

open about it,

that they can only inspect

about one to two percent

of that imported seafood.

So now you know that your

seafood is coming probably

from a foreign country.

It's going to be farm

raised, as well as wild.

And that when it

reaches this country,

only about one to two

percent of it is inspected.

The rest of it, you're

basically eating and hoping

that for the best,

that there aren't any

contaminants in it, any

types of pharmaceuticals,

any types of diseases,

because we just don't have

the capacity to inspect

all that seafood.

So what's the simple

answer to that?

It really is quite

simple, and that is,

go to your grocery store or

when you get your seafood,

buy U.S.-raised seafood.

Therefore, you know

where it's coming from.

Whether it's farm raised or

wild is up to you to decide,

but then if you look at it

and say, well farm raised,

I know the path from where

it came out as an egg

and grew up to my food,

you know that, that food

is heavily inspected

because the U.S. Department

of Agriculture and the FDA

looks at all of our food

and inspects it closely,

and you know that, that's

the food then that's landing

on your plate.

So it's a little promo there

for U.S. farm-raised

seafood actually.

It's the safest seafood

that's actually out there.

Now the other aspect I just

mentioned to you when I said,

well it's about even now

that the seafood you eat,

half of it is coming from farms,

and half of it's

coming from the wild.

Well the fact is, these

are the projections,

and what you can is, is

now that we're in 2015,

more and more of that seafood,

so the lighter colors up

here, is farm-raised seafood.

The darker colors

are the wild catch.

So in other words, farm-raised

seafood has actually

surpassed the amount

that's caught in the wild,

and that number, they only

expect to just keep increasing.

But that's kind of

an easy prediction.

You'll notice this has

kind of fallen flat.

I showed you the graph that

said nearly all the wild fish

that are out there

are fully exploited.

So where are they going

to get more of them?

They can't, the ocean's

just not producing it.

So as the demand goes

up, all of that demand

has to be met from

farm-raised fish.

All right?

Otherwise, there's

predictions out there,

and that is, well what about

the popularity of seafood?

Will it grow?

Will more people want seafood?

And the fact is, is

that about 45% of people

in 2009 were eating

farm-raised fish.

By 2030, they expect

that to equal up to 62%.

More and more people

are looking at seafood

saying, you know, when I read

about the health benefits,

there's a lot out there

that I like to hear.

It's really low in

polyunsaturated fatty acids.

It's really good for

your heart health.

It's really good for your

mental health.

So seafood overall, from

a nutritional perspective,

is a well-received,

well-respected

type of protein

that's out there.

And more and more people,

as they understand that,

are increasing their

intake of seafood.

Now you might look

at that and say,

well, that's a pretty

dramatic increase.

And it is.

The sad part is, is that

not much of that increase

comes from the United States.

We've been eating about

the same amount of seafood

over the past decade as

we are right now.

So the rest of the world

is increasing their uptake

of seafood.

Here in the U.S., we

generally look at it and say,

I eat my seafood once

a week, if you're good.

Once a month, if you

can afford it.

And we don't eat as much

as what the world is.

The world views seafood as

almost like their fast food,

where we kind of look at

it as more of a luxury meal

that we go out to a

restaurant to actually have.

Now if you remember when

I started on this path,

I said that the question

that's being asked

is where does aquaponics fit?

And I argued that it

fits into aquaculture.

Some people said, no, it's

really a subset of hydroponics

because isn't it really just

feeding plants raw nutrients

to get them to grow?

Well, partially.

But aquaponics does it in

a little more natural way

than what hydroponics does?

When you look at hydroponics,

and here's just a

schematic of it,

you basically have plants

growing in long trays.

And yes, their roots down

here are floating in water,

but that water is supplemented

with basically inorganic

minerals and nutrients.

So in other words,

they have to add up

a considerable amount of

macro and micro nutrients

that are obtained through

industrial or mining resources.

And then they mix

them up into a slurry,

and they spread them out in

the water that the plants

are growing in, so that they

can absorb these nutrients.

The problem with that is,

is industrial production

of nutrients is a very

energy inefficient

and polluting way of

producing nutrients.

And the other is, is mining

is just basically strip mining

these nutrients from

all across the globe.

And I'll talk a little bit

about that later on as well.

A lot of those nutrients

are not strip mined

in the United States, they're

done in foreign countries.

And those countries then

ship those into the U.S.

Well, they're strip mining

them and they're running

out of things such as

potassium, such as sulphur,

and therefore, they

control the market

where they raise the

prices for these nutrients,

and we just have to accept

it, so we can bring them in

as fertilizers.

There's a big issue there

that's kind of a

political issue, too,

because if there's a

country that dominates, say,

potassium mining, and we

have to buy from them,

well, they can make

demands upon our country

at that point.

Tell us that they

want us, therefore,

to export to them really

inexpensive U.S. goods

so that they will send

the potassium to us.

So there's kind of a

political play there as well

when it comes to

mining resources

and who controls the dollar.

The other aspect is, is

that it's a lot of nutrients

that they put into hydroponics.

In fact, they put in excess,

because they don't ever want

the plants wanting more.

And then the last is,

is that it's using up

finite resources.

These are exterior

resources being brought in,

flooded to these plants and

then essentially remixed

the next day and

done all over again.

So it's not a recycling

of natural resources.

It's really a

one-way flow pattern

when it comes to hydroponics.

And again, it's one of the

reasons why yes, aquaponics

kind of merges aquaculture

and hydroponics together,

but I think it

leans a lot heavier

on the aquaculture side than

it does on its relationship

to hydroponics.

Now if we look at a

typical aquaponics system,

it is just that.

It's integrated,

or a hybrid system

that contains on one

side your fish production

and on the other side, your

plant production.

So an aquaponics system

is really quite simple,

and that is, is that you

have the fish tanks here.

The fish spend their

entire life in those tanks.

This is where you feed them.

This is where you

watch them grow.

This is where you'll

harvest them from.

What they are

contributing to the system

is that they are

providing nutrients.

In a crude form, you could

say it's fish manure,

but it's raw nutrients they're

eliminating from their bodies

into the water.

Some of those nutrients

plants can use right away,

but most of them they can't.

So you have this middle

section right here

where you can see two terms:

one is called a clarifier,

and one is called a

mineralization tank.

I'll show you another

slide in a few minutes,

but what's taking place here

is that you have beneficial

bacteria growing in

these other tanks,

in these filter tanks.

And what the bacteria do, is

they convert the nutrients

that the fish are releasing

into an immediately usable form

for the plants.

Most people don't realize,

fish, 50% of their waste

is actually given

off as ammonia.

Well, ammonia would be

generally toxic to most plants

if you expose them to it.

But these bacteria

take the ammonia,

and they convert it into

nitrite and then nitrate.

So by the time the

water reaches over here,

where the plants are, it's

now in the form of nitrate

that the plants

readily take up.

Another aspect to it, which

is the mineralization tank,

is that fish just don't

release as waste potassium,

sulphur, magnesium and calcium.

They release fish manure.

But it has all of that in it.

So once again, there's

a whole other group

of beneficial bacteria that

decompose that solid waste.

And during decomposition,

they literally do release

the calcium, the magnesium,

the sulphates, the phosphates

into the water that then

travels over to where the plants

can absorb those nutrients.

So the little known

aspect about aquaponics

that people don't realize

is, yes, you're growing fish,

yes you're growing plants,

but you're also a

bacterial farmer,

because you need those

beneficial bacteria to complete

this conversion for you.

And they're, like I said, the

unsung heroes of aquaponics.

Once that conversion is

done, the water then goes

into your plant grow area,

which we'll talk about

a little bit more, depending

on what plants you're raising.

They absorb most

of those nutrients

and then that water

basically heads its way back

and goes back to the fish tanks,

where the fish get cleaner

water back to them, and

they renew this cycle

over and over again.

So talk about the fish

just a little bit.

We'll talk at the end,

we'll have questions.

I'll talk about the

fish a little bit here,

and that is when you

ask about aquaponics,

what I can tell you is, is

currently the king of aquaponics

is tilapia.

People raise them for

a variety of reasons,

which we'll just cover

a couple of them here.

But one of the reasons I

see, as a fish biologist,

that people like tilapia,

is that they are a very

forgiving fish.

In other words, you can

forget to turn that pump on

for a day, or you can go

on vacation for the weekend

and you'll come back and

you'll look in the tank,

and they'll have their little

fins up in the air like this

saying, we're okay.

(laughs)

I think that's probably the

main attraction for people

to use tilapia.

We can make mistakes while

we're trying to grow them,

and they'll still be there.

I put together just a

little chart over here

to show you why.

The reason for that is, is

that tilapia have very wide

tolerance ranges.

In other words, they can

stand different conditions

over a wide span.

Starting off with the first one.

They'll grow just fine

between the temperatures of 64

to 90 degrees.

Over 26 degrees, and

they'll handle it just fine.

All right?

You compare that

with any other fish

that we have around here, say

the native Wisconsin fish,

and they can withstand something

more in the range of about

five degree change, and then

they would just die.

So it's nice to have a fish

that'll take it easy on you

if the temperature changes.

The same goes for

oxygen, pH, ammonia,

which I spoke about already.

Nitrites, carbon dioxide.

This is a fish that has an

amazingly wide tolerance range

for almost all conditions.

And again, personally,

I feel that that's one

of the driving forces as

to why people like to raise

tilapia in aquaponics.

They're afraid to make

mistakes, and this is a fish

that basically will say to

you, it'll be all right.

We'll get through this together.

(laughs)

Right?

They also have another

feature about them

and that is, is that if you're

raising them in the range,

a temperature range they

like, you get remarkable

growth rates out of them.

In others words, you can

take a one-inch tilapia

and you can raise it to

about a pound and a half

to two pound tilapia in

about six months.

That's a rapid

turnaround for a fish.

But that helps in aquaponics

because it means that

you get a product out of

your system every six months.

And a lot of people, whether

they're feeding themselves

or their families, or whether

they are trying to sell them

to make this into a business,

it's good that you

get two crops a year

out of your protein source

in the system.

Now how does that differ?

Well, I'll talk about this

facility in a few minutes.

As Chris Cirmo mentioned,

the University of

Wisconsin-Stevens Point

opened the Aquaponics Innovation

Center this past April.

It was a really nice event

that kind of blew me away,

especially because

we had three days

where we opened the doors

and said, come on in and see

what it's all about.

And in three days, we had

700 people pass through

the facility, who all wanted

to know about aquaponics.

So really, it showed to me

there's a tremendous interest

out there, but it also

is kind of unique.

It catches people's eyes

as they walk through it.

And then they would get

kind of an excitement

to get into it.

One of the projects

we're trying to do

is we're trying to diversify

that fish crop.

Tilapia's good, it's forgiving.

It grows fast.

But if you wonder when you

see tilapia in the stores

and you see it on

a restaurant menu,

almost all the tilapia

that you're consuming

is a foreign import.

It comes from fish

farms elsewhere.

In fact, 90% of the tilapia

consumed in the U.S.

is foreign imports of tilapia.

And again, we kind of

covered that a little bit.

Who knows where's it's been,

where it hung out last night,

and who it was drinking

partner with during the course

of that night.

What's in that

tilapia at this point?

We don't know it comes

from a foreign country,

and it probably has not been

inspected by the FDA.

So one of the things that the

Aquaponics Innovation Center

is to do is to

diversify its fish crop.

And the angle we took

from it is, well,

why are we not raising in

these aquaponics systems

Wisconsin fish?

We've got quite a

number of fish here

that should grow

well in captivity,

so let's give it a try.

And one of the fish that we

started with here are Walleye.

Walleye show up on a lot

of menus around here,

especially on the

Friday night fish fry,

but it has always had

kind of a draw back,

and that is, is that Walleye

have always been farmed

in ponds.

And when you raise

a fish in a pond,

you suffer through this,

what do you want to call it,

four to six month

period known as winter?

(chuckles)

It really slows its growth down.

So it generally takes

a walleye farmer

about one to two years

to grow a walleye

from a small size to even

a one pound fish.

So what we have done is,

is we've moved them indoors

into the aquaponics system.

Now they're in a green house

where they're growing 365 days

out of the year.

And if you look at

the blue and the purple line,

this shows you the

growth that we're getting

between April, over a course

of a year essentially,

and we've been able to

get a one and a half

to one and three

quarter-pound walleye

to grow in a shorter

period of about

10 to 12 months.

Now fish farmers, aquaculture

growers, they like that.

That's at least one

product a year.

But then we're taking

it a step further,

and we took these walleye

and we basically mated them

with their cousin, the sauger,

and created what we

call hybrid walleyes.

Now somebody actually

asked me the other day

and they said, oh you're

creating the infamous

Frankenfish.

These are dangerous if

they ever get out there.

In this case, no we're not.

Because you can go fish

in the Mississippi River

and you can catch

a hybrid walleye.

Sauger and walleye actually

naturally reproduce

with one another.

So these fish exist in the wild.

We haven't created

really anything new.

We're just creating

them in captivity.

And then we added on here the

green and the orange lines

that are here.

And what we've been able

to do is these hybrid fish,

these hybrid walleye,

show advanced growth.

So we've been able to get

them to a one and a half

to two pound walleye

in nine months.

And this is all in

an aquaponics system.

So we basically label these

as our phase one, phase two

grow out periods.

They start out this

small, and over here,

they're a two-pound fish,

which is more than enough

for a nice platter on a

Friday night fish fry.

Most of that brought

about simply by moving

the whole process indoors

into a green house.

So we do think that there's

potential for introducing

more and more

types of local fish

into the aquaponics

production system,

and getting products out in

as little as nine months,

who knows, maybe if

we try something else,

we could even lower that

and get closer to that

six-month threshold

with tilapia.

So the potential is there,

and we have some early success

that's showing.

And then on the

other side of it,

you've got to look at plants.

Well, the nice thing

about aquaponics is,

is that you can raise

pretty much any plant

that you want to.

I just put them into four

major categories here,

which is leafy

greens, your lettuces,

your micro-greens, which

a lot of restaurants like.

Then your rooting crops; then

of course your fruiting crops.

You can raise any one

of them and all of them

in any type of

aquaponics system.

The only thing you

have to keep in mind

is your expectations.

What I can tell is, is that

your leafy greens like lettuce,

you can grow from a seed to

a nice full head of lettuce

in six weeks.

So that basically gives

you a rapid turnaround

for your crops in that system.

The microgreens, even shorter.

You need about two,

two and a half weeks,

and you can get microgreens

produced.

No problem there.

It's your root crops

and your fruit crops

that basically you've got to

give them a little more time.

Root crops, whether

they're radishes,

or onions can be grown in it,

but then you're talking about

something more along the lines

of about 10 to 12 weeks that

it's going to take them.

And of course, fruiting crops,

that's where you've got to

let the plant mature first

and flower, and then you've

got to let the flower

turn into the fruit.

So there you're looking

at something that

could be as short

as three months,

but more or less is

usually on the same cycle

as the tilapia and that

you'll get your crops

every six months.

So they're all,

possible in aquaponics,

it's just you have to

set your expectations

where you expect to

make those harvests

based on the plants

that you're growing.

Now I wanted to

bring it back to this,

and that is, is so you can

grow any plant that you want.

True, but the way or the

system of the aquaponics

that you raise them in has

to be a little different.

There are three plant production

systems in aquaponics.

The first one is known as

the nutrient film technique.

If you look at the

picture over here,

it should look a little

familiar from a previous slide.

That is what they raise

hydroponic crops in.

The concept is, is that

you just have a gutter,

and in that gutter

basically is pumped in

a little bit of water.

If you pop the top

off of the gutter,

there's about a quarter to

an eighth of an inch of water

streaming down the middle

of that gutter.

The plants' roots basically

kind of sway or flow into it

to pick up the nutrients.

Why am I talking about

nutrient film technique?

Because it still

exists in aquaponics

because it's the best way

to get hydroponic growers

to convert over to

aquaponics growers.

They already have

the infrastructure,

they just have to

add the fish into it

and stop adding in all

those inorganic nutrients

into it instead.

So it has a constant

flow of water.

It has a really

small amount of water

that has to flow

through the system,

since it's only about

a quarter to an eighth

of an inch thick.

But the disadvantages to it,

is that you need a biofilter.

Because that water coming

through it is so thin,

not only do the plant

roots grow in it,

but a lot of algae tends

to grow in it as well.

And you've got to

filter out that algae,

or they'll use up all

the nutrients right away,

and then your plants will

basically just start to die off.

So you have to have

some biofilter.

The other is, is that

you get lower yields

from the other systems

that I'll show you

because the plants are

nice and evenly spaced,

but you're limited by the

length of these gutters.

The other is, is if you

actually wanted to do aquaponics

with nutrient film

technique, you'd have to buy

the hydroponic components

or infrastructure,

and they tend to be very pricey.

So you would have a

higher startup cost there.

And overall, the system

is of a low stability.

And the reason for that is,

is that it has the least

amount of water in it

compared to the other systems

I'll show you because they

only have that quarter inch

of water flowing by the plants.

So if you were to add

a little bit of this

or a little bit of

that and then too much

of a third component,

there's too much of it

flowing through everything.

It doesn't get dilute

within the system.

The other is, is

that these plants,

because they're at a low density

and you have such little water,

the nutrient uptake

is relatively low,

which means nutrient-rich

water is returning back

to your fish, and they

can only withstand that

for a while before

they start to suffer

due to polluted

water conditions.

So like I said,

nutrient film technique,

generally a holdover

from hydroponics.

But some people like

it because it's clean,

it's compact, it fits

into a nice space,

and doesn't require

really that much water.

Another type is referred to

as the media grow beds.

And media grow beds,

as you can see here,

are essentially large channels

in which some type

of media or substrate

is put into the bottom of it.

There's really only one

requirement for that substrate,

and that is, is that it must

not dissolve in water.

Because the only thing

the substrate is doing,

is it's providing a surface

for the roots of the plants

to grab on to.

So where we see

media-based systems,

and you can see it

in this picture here,

is where you get tall plants.

Tall plants need

strong root structures,

and they hold on to the

substrate and the media

that's down there.

So if you start talking about

growing things, like I said,

corn, tomatoes, cucumbers,

you're going to want

a media-based system

because these plants need

to dig in to grow up.

As I put up here,

the advantages is,

the media that's in here

acts as the biofilter.

As the water flows through

pipes in the system,

that basically rains water out,

it's carrying some of

those waste products,

fish manure in them, and

they'll land in that media,

and the media will

cling on to them,

and then have

decomposition take place

right in the media bed.

So the solids are actually

found in the media,

but the other thing you find

is that if you dig in there,

and bring it up, you'll not

only come up with a handful

of media, but you'll come up

with a handful of fish manure.

And what's there as well are

the bacteria breaking it down.

So instead of having

a mineralization tank,

you actually have bacteria

growing down the bottom

of these media-based beds.

That helps compact the

space a little bit.

The disadvantages is, is

that you need a lot of water

flowing through the system.

You also have

difficulties when it comes

to maintenance and cleaning.

As I just said, dig your

hand down into that media,

and you'll come up with

fish manure and bacteria.

A lot of people don't

like the odor of that.

They don't like

the sight of that.

Well, if you want

to clean it out,

you pretty much have

to remove your plants,

hose down the

media, wash it out,

re-plant your plants and

start all over again.

So there's a high maintenance

cost when it comes to

these media-based systems.

And obviously here, as

you get those solids

from the fish manure

building up in here,

you can get clumps

of these manure,

which then basically channels

the water through the system.

And if your plants are

not growing anywhere

near the channel,

they start to droop

because they're not getting

all the water that they need.

On the flip side of it, is

that the nutrient uptake

by the plants is very high.

They're sitting right

there amongst the bacteria

having the conversion of

the nutrients done for them,

and they immediately

take up the nutrients.

So there's a rapid uptake of

nutrients in these systems,

and you get fairly rapid

growth of all these

different types of plants

that you're trying to grow.

And then that brings

us to the third type,

which is known as the

deep water culture,

or also known as

the raft system.

As more of a fish biologist

than a plant grower,

I always laugh when I

see deep water culture,

because these are basically

what they refer to

as large ponds or pools

that you're going to put

the plants in.

They're a foot deep.

Maybe for a botanist,

that's a deep water culture.

For a fish biologist,

I'm thinking thirty,

forty-feet deep.

(laughs)

So essentially,

they're a foot deep.

Where they get

their raft name from

is that you have Styrofoam

rafts that literally float

on top of that water,

and your plants are planted

in holes that poke through

the styrofoam.

The roots dangle down into this

deep pool full of nutrients,

and the plants grow on the

top side of that.

It's probably the most

common system in aquaponics

for raising the plants because

you can build these rafts

of any different sizes.

It's easy to float foam

right on top of the water.

And the other thing, as

you can see in the picture,

it's primarily used for

growing the leafy greens.

The ones that have a

six-week turnaround

from seed to harvest.

You can probably also

see the drawback.

I mean, why do they not use

these for growing tomato plants?

Well, the roots would grow

down into the deep water,

the plant would

grow up on the top,

as soon as the plant's top

growth is bigger than the roots,

it would flip over.

Because it's just

floating as a raft.

So they use shorter growing

plants such as the microgreens

and the leafy greens.

There's a constant flow

of water going through it.

You don't have to have an

enormous amount of water.

It basically sits in these

pools until the water

gets replenished by a pump.

And it's easy to

maintain and clean

because you literally

just lift up the rafts,

scrub them down.

If the deep water looks

dirty, you flush it out.

You fill it with more water

and you seal it back up again

and it's all ready to grow.

And you can do that in

an hour or so.

You may need a biofilter.

Another nice thing about

it is the bacteria,

those beneficial bacteria

really like to grow

in these deep water cultures.

But sometimes, it's not enough.

You need more of the bacteria.

So you may actually have

to have one of those

mineralization tanks.

There is a large volume

of water going through it.

You can also aerate the roots,

so that you get

healthy root growth,

which usually leads to

healthy leafy growth,

and the nutrient uptake by the

plants is really, really high

in these systems.

So again, they are

the most common.

They're the most talked

about and studied

not only because they seem

to be the most efficient

and productive, but

on the flip side,

you have to look at it and say,

I can't grow all the

different crops I want.

I can only grow those

that will float on top

of these rafts and not

turn the thing over

and drown out all your plants.

Now I didn't forget about them,

and I wanted to come

back and that is,

whether you call them

beneficial bacteria

or you call them

aquaponic biofilm,

you have to remember that if

you're an aquaponic producer,

you're growing the fish and

you're growing the plants,

which you can see, but you're

also cultivating bacteria.

Before you look at that and

say, wow, those bacteria

they look fascinating.

No, that's just plastic.

The brown, goopy stuff?

That's the bacteria.

All the plastic does is,

is that if you didn't give

the bacteria something

to hold on to,

it would be going

on a water park ride

all throughout your

aquaponics system

and suffering pretty bad.

You want them to sit still

and you want them to do

the conversions that you want,

so you just give them things

like plastic to hold on to.

And then they'll stay in

your filtration systems

or your filtration tanks.

What are they?

Well, there's their official

name in case you wanted

to memorize it for the quiz

after the presentation.

Nitrifying autotrophic

bacteria consortium.

Sounds intimidating, actually.

(laughs)

It's made up of two groups:

the nitroso-bacteria

and the nitro-bacteria.

What do they do?

Well, as I mentioned

before, fish give off a lot

of their waste in

the form of ammonia.

What do we know about ammonia?

It's highly toxic to fish,

and it's very toxic to plants.

That would shut down your

aquaponics system in an instant.

So instead, your

nitroso-bacteria group

essentially converts

it to nitrite,

an important step because

fish are a lot more tolerant

to nitrite, and some plants

don't mind taking up nitrite

and they do further conversion

in their roots to nitrate.

But luckily, we have the

nitro-bacteria here as well,

and they complete the conversion

of nitrite to nitrate.

What's beneficial about that?

That's the form of nitrogen

that plants will readily

uptake and automatically

put it into actual growth.

And the other thing is,

is fish are very tolerant

of high nitrate levels.

So if they do build

up in your system

because the plants aren't

taking the nitrates up

fast enough, it doesn't matter.

It's just like water

over the fish's back.

It'll just pass right

by them in the water.

It's not toxic to them, except

at extremely high levels,

which are usually

never achieved.

So always keep that in mind.

If you ever visit an

aquaponics facility,

most of the growers will

show off their fish,

they'll show you

the little ones,

they'll show you the big ones

and they'll say, look at

the growth we're getting.

Then they'll show you the

plants and they'll say,

do you want to try

some and taste it?

Now you know the secret,

walk up to them and say, yeah,

that's all well and good,

but show me the real

stars of the system.

Show me the bacteria.

They'll probably either

look at you very funny

or kick you out.

(laughs)

But they'll immediately know,

you know a lot about

aquaponics at that point,

because that's really

the star of the system.

Without their conversion,

the whole system of fish

and plants doesn't work.

And that basically

brings full circle,

this aquaponics cycle.

It's a symbiotic

relationship, as you now know,

between fish, microorganisms

and plants.

Each one of them feeding

off of the next one

and replenishing the water

in the system.

The other aspect about it,

and I've heard so many

talks by different

aquaponics scientists,

is they said,

aquaculture has some drawbacks.

Especially if you talk

about recycling aquaculture.

Well, why is that?

We just covered it.

Fish produce ammonia,

which is toxic to them.

So aquaculture spends an

enormous amount of time

either mechanically or

chemically trying to get ammonia

out of the system.

And it's a tough thing to do.

On the hydroponics side,

the negative part is, is

you're totally dependent

upon industrialized or

mined minerals and nutrients

to put into your system.

If the shipment comes late,

or if the price goes up,

it impacts your

hydroponic system.

But if you take the

best of those worlds,

the fish and the plants,

put them together

with the bacteria,

all of a sudden,

everything seems to hit this

symbiosis or equilibrium.

The fish are producing

the minerals,

the minerals are

converted by the bacteria,

the plants absorb the minerals,

and the water goes right

back to the fish.

And most aquaculturists,

most aquaponic growers

will look at you and you'll say,

well how is that possible?

And they said, I don't know,

it just happens.

It's amazing how the

three of these organisms,

or group of organisms,

relate to one another

and help each other out.

I put together a

little slide here,

and these are some

of the answers

I've heard these experts say.

They've said, why

does it work?

As a scientist, you can't

just sit there and say,

wow that sounds great, it's

a symbiotic relationship,

let's all watch

them sing Kumbaya,

and everybody will grow nicely.

But scientists say, but

why does it work.

Well, one of the things

is, is that you get this

optimal ratio between the

fish and the plants.

It's based upon that

nutrient uptake.

I put this little table

together over here

because as a scientist, I

want to know the answers

to why it works.

What I did was, is I took a

label off of a bag of fish food.

And those are the

ingredients that they listed

on that label.

And then I picked out

my book on plant growth

and horticulture,

and I put down a list

of all the minerals and

nutrients that a plant

needs to grow.

Just take a look at that list.

All the same, until you get

down to this level right here.

Now one of them I

highlighted on the bottom,

that is plants need nitrogen

while fish waste contains

protein, protein is

made up of nitrogen,

so the plants are

getting the nitrogen.

So it's really this

little group here.

The plants are not getting

all the boron, molybdenum

and sulphur that they

could possibly want

that you would have to monitor.

Well, the nice thing is, is

those three have asterisks

because they're

micro-nutrients for plants.

In other words, they need

trace quantities.

And it actually turns out

that there may be a chance

that the water you're

putting into the system,

say, from a well, already

contains trace quantities

of these micro-nutrients.

So there have been very

little studies or reports

that have come out that have

said aquaponics didn't work

because my boron or

molybdenum was too low.

Most people find it

actually finds its way

into the system.

There have been a

couple that have said

you may have to supplement

just little trace quantities

of sulphur into the system,

but it really depends

upon what fish you're

growing since the source

is the fish food for

these nutrients.

This is tilapia food,

there are some fish foods

that have a little

bit of sulphur in them

so they may be

getting it anyhow.

And if you're wondering, the

cobalt, selenium and iodine,

those are trace elements

in fish food anyhow,

so they're not accumulating

within the system.

The plants aren't using

them, and they probably,

through evaporation, through

cleaning of the system,

you'll probably flush

them out anyhow.

So that's one aspect of it.

Again, what they find is,

is that for aquaponics

to work efficiently, you

have to feed about 60

to 100 grams of

fish food per day

to a square meter of

plants that you're growing

within the system.

Turns out that if you

compare that to aquaculture,

that's actually a

really low feeding rate.

So technically, you

can underfeed your fish

in an aquaponics system

and still get abundant

plant growth.

Now I'm not saying

you should do that

because you probably also

want to harvest your fish

after a while.

So you're probably feeding

the fish all they need,

and the plants are actually

getting an abundance

of nutrients that they need.

But that right

balance as I mentioned

is really based upon

a couple of things.

The types of fish

that you're growing,

the plant growth

platform, whether it

was the nutrient film,

the media-based or the raft,

as well as the type of plant.

Some plants such as

your flowering plants

won't actually set fruit

unless they have higher

or elevated levels of

nitrate in the system.

So you may actually have to

increase your fish feeding

to get that spike in nitrate

and then your flowering

plants will suddenly start

to grow their fruits on them.

And then it also depends on

your chemical composition

of the water.

Again, where are you getting

your water source from?

Does it have boron, molybdenum

or suplhur already in it,

So it's always good to get

a water chemistry test done

of your well water to figure out

what all the compounds are

that are inside of it.

And again, the study we're

doing now with those walleye,

to me, is going to be

an intriguing study.

Because tilapia are more

kind of like the herbivores,

but walleye are

obviously carnivores.

Therefore, what's in their

diet or in their fish food

is dramatically different

between the two of them.

I wish I could stand

here and show you,

now here's the results,

but our walleye are now

four months old.

And I told you they have

to grow 10 to 12 months,

and we've been harvesting

plants out of the system

at actually the same

rate as the tilapia.

So it appears the plants

are getting what they need,

but we're kind of looking

to see if their nutrient

composition is a

little different.

You'll just have

stay tuned for that,

we still got at least

another six months

before we've got the results

from that to share with you.

And then the other

part I mentioned is,

is that it allows for

year-round farming.

And that shouldn't be ignored.

If you're living

down, say, in Florida,

they already do year-round

agricultural production

down there.

But as I said, how

nice would it be

to walk into a greenhouse

in the middle of January

or February in Wisconsin

and hand-pick your fresh,

well, I shy away from

picking cucumbers,

but your hand-picked

tomatoes or your corn

or your peppers that

are growing right there

in the middle of February

in this tropical environment

in the middle of Wisconsin?

So it has a lot

of potential there

to get people back to

eating their fresh fruits

and vegetables in

the middle of winter,

that were grown right next door.

And again, I don't want to

make it sound like aquaponics

is the savior of all.

Aquaponics is a compromise.

Again, putting the

major players up there.

Consider their tolerances.

As I mentioned, the fish are

between 60 to 80 degrees.

There's also pH, they

like seven to eight.

If we look at plants,

most plants like 60 to 80.

Hey, there's a good

match-up right there.

On the other hand, plants

actually prefer a pH

that's a little

acidic, fish don't.

Uh oh, they're not directly

on par with one another.

Well, don't forget these

guys, the beneficial bacteria,

you're farming them as well.

And what you see is, is there

were two different groups

of bacteria, one doing

the ammonia to nitrite,

another doing the

nitrite to nitrate.

Well, the nitrous ammonus

is pretty good, 68 to 86

and 7.8 to eight.

That matches up

well with the fish.

But those nitrobacter converting

the nitrite to nitrate,

they're heat lovers.

They really want that system

running at a much

higher temperature.

And as you can see, their

pH is pretty neutral.

So if you really look at

all three of those crops

you're raising, you have

to have to pick something

to set your

aquaponics system at.

I mean, what temperature

do you want it at?

What pH do you

want the water at?

Turns out that what most

aquaponics operates at

is a compromise.

It's about 70 to 80

degrees Fahrenheit

and about a pH of

seven or neutral.

What does it mean?

Well, it means you

can do aquaponics.

You can grow fish,

plants and bacteria.

But you're probably

not going to grow them

at the fastest rate

possible.

You have to set

your expectations

right where they

need to be, which is,

I'll get great growth, I

won't get super great growth

out of my system, because

everything is being compromised

a little bit.

And that's something

to keep in mind.

As I said, it's not the

answer to all the problems,

but it is one of the

potential solutions.

Another question, and I

actually was asked this,

this morning on the radio,

and that is somebody

said to me, well,

but who's doing aquaponics?

Is this just for that person

who wants something set up

in their garage?

Or is this an

industrial complex?

Well, my answer is, is that

aquaponics is scalable.

I suggest anybody

getting into it,

gets into it on a small scale.

Set up your own home

or hobby system,

in your backyard

or in your garage,

and have some fun with it.

Try the fish and the

plants and try to match up

what you'd like to grow and

what is a good compromise.

Most people get

into it that way.

And what they find is, is

they're suddenly raising

a lot more vegetables

than they can eat.

So that takes it to the

next one and they say,

well, if I'm doing that, I

might as well start selling

some of it.

So they go to the Farmer's

Market, a nice local market,

where they can sell

all their crops.

The next thing you know,

their system has outgrown

their little shed and it's

sticking now into their lawn.

And now they're into a

slightly larger size system.

They also look at that and say,

well, a lot of people

stop by and want to see

what it is I'm doing.

So now we get into the social

and community aquaponics.

One of the more famous

ones is right here,

it's Growing Power in Milwaukee.

They get people in

their own neighborhoods

to grow their own food, to

get a job at the location,

and see that their

food is actually coming

from just down the block.

Well, now you got all

the neighbors involved,

and they're all interested

and you're starting

to build up a staff.

So now you got a commercial

food production at that point

and you start getting all

these fish tanks set up

and you start setting

up hundreds of feet

of plant production.

And what you find is,

is that all these people

that were interested,

the Farmer's Market you

started selling it at,

suddenly, people are

knocking down your door.

They're ringing the doorbell,

they're sending the email

saying, but I want more.

So you've increased the

size of your production.

But as I said before,

it's scalable.