I’ve recently finished my second windowfarm project with fourth grade elementary school children, and I’ve discovered an incredible new world. After seeing  Britta Riley’s TED lecture, I figured I really should try and build an aquaponic windowfarm system with the children I teach.

The difference this time was that we’ve decided to go at it as a project based course (PBL). 14 meetings, 75 minutes each. We’ve started by planning the system together, acquiring the materials, building the system- including a wooden hanging rack, taking care of the plants, the fish, and the pumps. After the system was set up we’ve started following the plants’ growth. We’ve had 2 columns  running to a fish aquarium with 5 goldfish, and one column with a bucket with water and fertilizer. Each column had different types of plants to compare their growth rate. The children were in charge of everything – taking care of the windowfarm, following the farm as it evolves (plants & fish), documenting the process, and finally presenting all they did to their parents over a glass of farm-grown mint tea .

It was an incredible success.

I’d love to share with you some of the insights

Nadav

Hello, I discovered this website through TED, where I watched a talk by Britta Riley about window farming. As soon as I heard that window farmers have been able to grow strawberries that fruited for 9 months under low-light conditions, I was hooked. I am eager to get started on creating my own window farm.

I looked at the instructions for window farms 3.0, here, briefly. My first questions regard the use of plastic water bottles.

I did a quick search on the internet and found that plastic water bottles are typically made of Polyethylene terephthalate, commonly referred to as PETE or PET. Then, remembering hearing that plastic water bottles should not be reused, I did another quick search on what compounds are released when water is stored in plastic bottles for “too long” and what accelerates the rate of release of such compounds. The main thing I found was that dioxins are released by plastic water bottles, and doixins have been found to cause breast cancer in women, but I’m sure dioxins do not just affect women. I did another quick search on plant up-take of dioxins, and found that there is substantial literature regarding this issue as a health concern for humans. Not knowing the chemical structure of dioxins or their properties, I do not know what kinds of chemicals can be used to either chemically alter the dioxins into a safe form or to “sop up” the dioxins so plant up-take is reduced or eliminated.

My questions, then, are:

Is it safe to have plants growing in PETE bottles, with water constantly running through the bottles, extracting dioxins?

Is there a safer plastic to use than PETE, or another composition overall, for example glass?

Please do not hesitate to answer any of these questions (especially the last one) with something technically challenging (for example, using glass bottles would be difficult because cutting the glass would present a challenge). I will consider technical limitations at a later time.

Thank you!

Depois de meus peixinhos morrerem de uma vez só, denovo, desisti de criá-los por enquanto e resolvi usar o aquário para outra coisa:

Montei uma windowfarm com garrafas de água mineral reaproveitadas e vasinhos plásticos. O sistema de irrigação foi constriudo com uma bomba de água de parabrisas de carro e mangueiras de aquário. E para automatizar o sistema estreiei meu garduino na protoboard!

É tudo novo pra mim, o arduino e sua programação e também o cultivo hidropônico. Estou bem entusiasmado com os resultados até agora…

Mais infos aqui: http://wiki.nosdigitais.teia.org.br/Garduino

Here is a recent photo.  All of the components are together and working well finally.

It’s powered with an 8 outlet air pump (I’m only using 6).

http://www.hydroasis.com/hy/productdetail.aspx?id=1183#

Here is my spin in the basic window farm design, with additional lighting added due to the lack of sunny days in Portland Oregon this time of year.

The water/nutrient source is from an already established planted aquarium that is also my coffee table.

Indoor aquaponic window farm

I’ll be adding 4 more columns, 2 in each of the side windows.  The water supply line is extra high above the pots to allow room for additional pots later.  The completed system allows for 24-30 pots.

Custom hanging design

I used alligator clips with S hooks to hang the pots.  I went with white nylon cord to match the white pots.  The cord can be found at general Walmart type stores for really cheap, it’s more expensive at hardware stores.

Close up of pot and drip tube.

I went with an open pot design for aesthetic reasons.  I shopped around for something better looking than bottles, but I couldn’t find anything I liked that wasn’t overly expensive.  To take care of the splashing issue of water dropping from pot to pot, I added air tubing to guide the water flow.  This also allows me to place seedlings in the center of the pot, and place the water outlet to the side, to keep the seedlings from getting beaten up from the impact of the dripping water.

Closeup of how I added a reflector to the fluorescent light.

For an extra kick of light during the fall/winter session I added a T5 florescent light.  To keep the light from lighting up my entire place, I added a reflector to direct the light out sideways which also pushes more light towards the plants.  Using 2 elbow brackets, and a piece of roof flashing from the hardware store, it was easy to put together.  I’m going to spray paint the reflector with white primer to match the rest of the design.

More info coming soon….

This system was built in less than a day and additionally:

• Combines aquarium aeration with the air pump.
• Pushes water up 202cm (6.6 feet) with a 1.5 litre/hour pump (I don’t think pump size matters at all here, this one cost R60, or about $8).
• Moves roughly 100-120ml in 6 hours (I think that’s how much I slept last night).
• (Accidental) varying dripping time.
• You can probably run many ‘percolators’ off one pump by splitting the air feed, or using a very long aeration stone.
• The system runs very quiet (The air pump makes more noise than the gurgling).
• The top 500ml bottle can be converted to a baffle or silencer quite easily.
• It may possibly even be converted to a non aquaponic pump?
• No pump-strain, T-junctions, valves or needles (or things that look like them, I’m a wuss, ok?)

We started the apartment search process and I think we may have found a great place but not sure when we will get to make our move.  The apartment has a huge (and I do mean huge) wrap around patio with a fence around it and if I can get an apartment where that patio faces south we will be all set for the Aquaponics system of my dreams.

I will put plastic tubs along the edge of the patio and put trout and perch fingerlings in them.  Then will rig them up with a two tiered system of grow beds with gravity drip and a pump in each fish tub.  This way I can grow root crops also.  Then I will hang the window farm in the space above those grow beds all the way from the top of the patio roof.  Could be about 6-8 bottles each row and probably 15 rows.  I will pump the water clear to the top of the windowfarm and let it drip through the grow beds and back into the fishtubs.  I can hang plastic around the whole thing in the winter to make a greenhouse.

So what have I missed and what problems do you all forsee with this plan.

I would appreciate your feedback so I can set this all up with not too many redo steps.  Also does anyone have a reliable ratio number for fish to plants and can you just start small and grow slowly to keep it balanced, or is that exactly the worst thing to do?

Thanks for your input.

Pam

Sorry to be bombarding you with these pictures, if you’re uninterested.

So, I’m just a few days away from the science fair, and I’m already disappointed in how rigourous I was not.  If I do this for next year, I’ve got some ideas of how to really science this up.

That having been said, I’ve got the

This pea blossom is in one of the 2 "just fish water" columns.

This pea blossom is in the "CO2" column.

first blossoms from my pea plants!

The first pic, you can’t really see the blossom, but it’s in there.  It’s the whitish ‘leaf’ right just up and left from centre.

The CO2 column has only been getting CO2 for the last 4 or 5 days, so there shouldn’t be loads of difference yet, even if I’m getting a meaningful amount in there.

How am I putting CO2 into this column of plants, you ask?

Read on…

If you have an aquarium that’s heavily planted with real plants, you have a nice, natural support to your filtration.  Unfortunately, the heavier the plant load, the more you run up against a limit on the plants’ growth – the amount of available CO2 in the water.  Since the concentration of CO2 will be roughly equivalent to that in the atmosphere, since the fish are not as great producer of CO2 as land animals, CO2 supplementation helps encourage plant growth.  Now you can spend LOADS of cash on a CO2 canister with all the bells and whistles ($00s of dollars) or you can have some soda pop, and DIY a CO2 generator.

2 cups of brown sugar, spooned oh-so-slowly into a pop bottle

drill a hole 1/16" smaller than the outer diameter of the airline. Cut the airline at an angle to make threading easier. Once you've got it in, hot glue a seal on both sides of the cap.

1 tsp of quick yeast (you can go as high as 1 tbsp, some say) and 1 litre of water. Don't slop the yeast on the sides of the bottle, it won't do much good there.

One nice thing about doing this instead for hydroponics instead of for an aquarium is that for the latter you need a fancy diffuser (there are, of course, DIY options).

So I just have the other end of the CO2 airline going into the top of the bag that’s around one of my plant columns.  Simple.

So, my experiment was ‘is fish water as  good as commercial hydroponics fertilizer’.  There are a few caveats to my investigation.  #1 is that I’m not stocking at true Aquaponics densities.  They fill their tanks to the gills (heh.  Get it?  To the gills.  It’s about fish) and so have a much higher nitrogen level than I have.   They would also spread this over many more plants than I am.  There’s a lot of variables, is what I’m saying.  At any rate, here’s a few examples of the growth.

taken March 23rd

taken April 3rd

Not a bad amount of growth for… what, 12 days?

That’s it for tonight. Thanks for your interest, and have a good night. Good luck with your veggies.

So, she’s running a beaut now.  I’ve got 3 columns of fish water running, and 1 of retail nutrient solution (I can get the name if you care.

I germinated seeds about 3 weeks ago, and now I’ve got all four columns running 2 very substantial bean plants each (last pics are from 10 days ago.  I’m afraid to look in the silver cube) and a mediocre pea plant.

I still haven’t put in the CO2 doping yet.  TOmorrow?  So.. .

That's aluminized plastic (cheap emergency heat blanket) around the frame. Keeps the light nice and bright inside.

Tired…

I’ll type more about what you’re looking at soon.  Promise!  I’ve just been putting this off so long I have to do something.

If this is in the wrong space, let me know, and I’ll publish further steps of construction somewhere else.

I had a productive weekend, and things worked the way they should have.  I didn’t get as much done as I would have liked, but there you go.  That’s doing things for the first time for you.  You learn all sorts of stuff about unrealistic expectations. Read the rest of this entry →

One year and 3 months ago I started fishkeeping as a Phase 1 of trying to do home Aquaponics, inspired by the work of the people that did the Ark project out of (I think) Rhode Island (can’t find it now).

Of course, I thought I was real smart, and the only one to do this.

Then I saw the Windowfarms thing, and found this community and was a little dejected I wasn’t as smrt as I thought.

Regardless, I got into fishkeeping in a fairly big way, and have a number of beautiful tanks I just love watching.  I had totally forgotten about the aquaponics side of my plan until I heard about a science fair for adults (complete with category for best Volcano) coming in April.  So I quickly geared up to prepare an experiment for Aquaponics.  I’m just using the fish water for the hydroponic side, not looking to eat the fish, so I’m calling this AquaponicsLite.  I’ve got almost all of my equipment and materials, tonight I’ll be getting the last of the wood to set up the plant stand, and then I’ll be good to go.

The experiment is monitoring electrical usage to see how cost/energy efficient the process is.  I won’t be using sunlight because I’ll also be monitoring quality of growth given 3 variables.

• Control group of hydroponics, bagged to maintain humidity
• Hydroponics with CO2 supplementation
• Soil
• One unbagged to see effects of no humidity control.

So, I’ve gotten a few pictures, but I’ll get more once I’ve finished the set up and it’s all there in it’s magical glory.  I’m posting this here to get things started.

BTW: running a fish tank with heater, 2 t5HO lights and 2 HOB filters for a week  costs ~$1.50 at $0.0064/kwH.