Public Greenhouse aquaponics system proposal.

[James Keller]

So here is my sketchup for a system I've designed.  Background: There is a new vertical greenhouse that will be built in downtown Jackson, WY.  It will be on a 4500 sq ft plot, and go up 3 stories.  (verticalharvest.org)  The public will be allowed access to the first floor, and the top 2 floors are going to be used to grow hydroponic vegetables.  

My idea is to get an aquaponic system in the greenhouse for public education and to build interest in aquaponics.  

I would propose that they set aside roughly a 10' by 10' space for this project.  My design has a few unique factors, first is the L shaped fish tank in the foreground, which will house native trout, and be set up to mimic the trout's natural habitat.  Also, I chose to separate the grow beds into 3 different types of bed (flood and drain on the left, constant flood in the middle and a float bed on the right).  

The initial issue I foresee is how to keep this water cold enough for the fish - are there water chillers out there that could cool the roughly 300 gallon fish tank?  Also, would the vegetable plants dislike 45 or colder water temps?  I know these trout need highly oxegenated water, but I haven't built any kind of aeration into this system yet.  

I have no idea if they will even look at this idea, but I think it will be worth at least nailing down a design and then attempting to present it to the people who are building this greenhouse.  I designed this fairly quickly today, so any comments on this design would be welcome!  

[James Keller]

Hey Mark - the 3d drawing is done using Google Sketchup - it's free to download and has tutorials to help you along.  Those tomato plants were just the first thing I downloaded into the model to make it look a little more like an AP setup.  I don't know yet what we would plan to grow.  

As for the support, I agree with what Bob Campbell wrote on Monday - we will use common materials that you could pick up at local stores, and therefore, the setup will eventually look different than what I've posted as pictures along the way.  I am just doing these mockups as conceptual ideas, and they will serve as the jumping-off point.

In terms of flow - the way it's set up now would be best suited for a continuous flow grow bed set up, with one pump running 24/7.  This will be the simplest and also best way to provide enough constant oxygenation for the trout.  I have a system that is a month old now, and had been running it as a fill and drain with a bell siphon.  However, because I want to propose this system as a continuous flow, I decided to take the bell siphon out of the system to see what happened.  I went away for 3 days and came back yesterday, and was happy to see that the plants were all still doing fine, arguably better, than when i had them on fill and drain.  I was worried about "drowning" the roots, but everything still looks very happy.

James

Mark Berger said:

James,

Your design looks nice. A fewquestions: do you plan to grow tomatoes per the drawing? Won't the tomato plant need much warmer water than what the trout will like? Also, I did not see any structural support for the system. While very space efficient, I am concerned that your grow beds may buckle without enough support. The grow bed will employ what type of aquaponics? Flood and drain or just continuous flow?

Finally, how did you create the 3d mockup? I would like to make one for my greenhouse design and show it to you.

Mark

[Mark Berger]

I suppose if you your water is highly oxygenated for the trout, that makes the plants happy, even if they are underwater all day.

How did you quickly switch from ebb&flow to continuous flow? Did you simply remove the bell house of the siphon and let water flow down the drain pipe?

[TCLynx]

Yep constant flow/constant flood works as long as water is well aerated and the flow rate is high enough to keep things nice for the plants.

An easy way to switch to constant flood is to simply remove the bell if you are running bell siphons.  If running timed flood and drain you simply turn the pump on full time and you might change out the stand pips so they have no holes at the bottoms if you were to add more water to the system but the power goes out and the grow beds drain, you would overflow the sump or fish tank.

[James Keller]

Yup, simply removed the bell and the water runs right down the drain pipe that was already there.  

An unrelated question to the forum:  as part of this discussion thread - per Chris' suggestion to use an SLO - I fashioned one in my current system.  It collects the brown stuff at the bottom, I'm guessing mainly poo and definitely uneaten sunken food pellets.  I'm able to "collect" it because my bio filter setup has a drain valve.  I'm wondering if this is the kind of stuff that would be good for either worm food or using it to water potted plants, for an extra nutrient kick.  Or is this the stuff that needs to be completely thrown out? 

[TCLynx]

oh worms love the stuff.

and if it doesn't smell too bad, you might dilute it a little and use for potted plants.

[Bob Campbell]

Here is a link to a post I recently made on my blog about affordable tanks and grow media.

I think the key to getting more people involved in aquaponics is to show something others can duplicate easily.

These tanks are study and well priced.  The grow media is by far the least expensive I have found.

[James Keller]

So after talking with some of the people that have been involved with this greenhouse, I've submitted the following schematic as the proposal for the greenhouse aquaponics system.  Hope to hear back soon!

All of this can be bought at a local store or on Amazon.  Initial cost will be about $500 and the only running cost will be the pump on 24/7.  I will be building this in my basement with grow lights as the only addition in the meantime (when my roommate moves out soon).  

[Jim Troyer]

Looks nice - what will you do for water aeration?

[TCLynx]

There are a few other running costs you missed.

Water

Fish

Fish food

Seeds/plants

Water test kit

pH buffers like calcium carbonate and potassium bicarbonate. and possibly some chelated iron supplement and seaweed extract

And probably a bag of cheap salt to salt the system for when you first get the fish.

[Mark Berger]

I would be concerned with so many trout in only 100 gallons.

[TCLynx]

Yea, I too would probably go for less fish in a 100 gallon tank.

[James Keller]

Thanks TC - Sorry for the quick and possibly confusing post, but yes, there will definitely be other costs such as those you listed below that I did mention in the email that was sent.  Water will probably be provided in this greenhouse, so minimal, as will the seeds for plants.  Fish food will definitely be the largest expense here, and the water test kits/supplements and other random items were included in the initial cost.  As for trout stocking density, what would the forum recommend here?  I think I may have gone a little on the high side as a starting point, and there is also the chance that we start with a 150 gallon tank.  

Jim - I was thinking of air pumps/stones as aeration throughout the system, which will add to the cost a bit.  But in the interest of simplicity for this proposal, I left those details out for the moment.  Anything else I'm missing?

Thanks! James

TCLynx said:

There are a few other running costs you missed.

Water

Fish

Fish food

Seeds/plants

Water test kit

pH buffers like calcium carbonate and potassium bicarbonate. and possibly some chelated iron supplement and seaweed extract

And probably a bag of cheap salt to salt the system for when you first get the fish.