Easy Aquaponics from "mostly" re-purposed materials

Okay folks - let me have it. My first Instructable was some time ago and it wasn't much so I thought to myself, "how can I really bring some value to the community" and this is what I came up with. My son (15) and I built this over two weekends. Granted, if you had the supplies ready and handy, you could easily do it in a day if you really hunkered down.

Without further delay, I present to you our (roughly) 200 gallon aquaponics system, built from re-purposed wood, a cheap pond kit, some PVC, and lava rocks.

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Step 1: Tearing down the old raised beds and getting the base built

What really prompted this project was the fact I was getting very tired of the fire ants getting into my raised beds. After losing much of my crops to ants, I decided I was going to grow in water via hydroponics. Then, I learned about Aquaponics and it was on.

Thanks to the help of my son, all of the 6" screws were taken out of these timbers, we cut them to size and ultimately built a smaller version for the tank and used some of the pieces for legs and supports on the grow bed.  It is worth noting that we were able to reuse most of the screws that came out of the timbers as well so I did not have to buy any. 

The size of my grow bed and the size of my tank were based on mathematical calculations made by me based on the amount of pond liner I had available to me. I bought the kit (see picture) on Craigslist for $25 - it was still brand new in the box. The liner was 8x10 so I had to figure on how much I could use of this. I elected to build a tank that was 2x7 x18" deep and row bed was 1x7 x1' deep for optimal root space. Of course, if you are using a different size liner, just keep in mind that your depth will take off length and width from ALL sides (if you go 1' deep, you need to take off 2' from length and width, which works out to 1' all the way around)

damionflynn (author) 11 months ago
It has been almost 4 weeks since we built the system and the system is leveling out and over the past week, the tomatoes have just taken off. The strawberries never grew so I think the roots we got may have been bad, c'est la vie. Anyways, thought I would post an update :)
RROAMM7 months ago
Very nice project and I am glad I ran across it. I am getting ready to build my system this winter and I have a question or two.
1. how is the volcanic rock working (is it just cinder rock?). I ask because i have a huge area of volcanic rock that the previous owner installed (20 ft X 60ft) and I would love to put it to better use.
2. did you screen it down to a specific size? if so what size?
3. did you pre-rinse the rock before installing?
4. does it affect water chemistry? or the fish ?
Thank you for the instructable
damionflynn (author)  RROAMM7 months ago
Thank you and glad to answer questions :)
1. Not sure the difference of the rock - this is the stuff you buy at Home Depot for about $7-$8/bag that many people use in their beds so I assume it is the same stuff.
2. Not really. We rinsed it off and did not worry about the exceptionally small bits but we did not specifically screen it.
3. Yes. We did this mostly for water clarity though. I am not aware of any chemicals in these rocks. We did it so the water would not take as long to get the red out.
4. I have noticed no ill-effects.

One thing I can say is that if I were getting the rocks free or already had them, I would use them again. I would give second thought to using them if I were paying for them though. Initially I used the Lava rocks for cost and weight (they are much lighter than the same volume of neutral ph gravel/river pebbles). The downside I notice is that when you have to remove plants it can be a chore because the roots really grab on to the porous rocks.
Good attributes allow for more bacteria though so I believe the water gets cleaned faster and allows for a little more plants in the same area, but I have no conclusive data to support that.

All in all it has been an excellent system and I have pulled probably close to 10 gallons of Romano tomatoes off one plant, at least a dozen cantaloupe, close to a hundred cucumbers, numerous strawberries (uncountable as my daughter (6) usually gets to them before I know about it), and more. I found that peppers and zucchini do not do well in the system. Leafy greens should flourish but I have yet to attempt any.
Nice system, I like your use of the verticle grow-pipes.
Volcanic rock is good due to its porous attributes; lots of hidey holes for happy bacteria. The best for aquaponics is expanded clay which, like the volcanic rock is porous, but has the added attributes of being smaller (0.5 inch-ish) and lighter. It does have the down side of being more expensive though (avoid the ultra-cheap stuff; it crumbles very easily and takes forever to stop floating (weeks if you're unlucky).
damionflynn (author)  samueljim5 months ago
Thank you. for your comment/feedback.
I chose the lava rock because I knew it would work, was lighter than gravel to fill the same area, and quite frankly, because it was easy to find locally (expanded clay is not available in my local area anywhere I could find).

It has done very well in the system but can be cumbersome removing the plants because the roots get tangled in them because of their super-porous nature.
Thank you, great information. It looks like I will be able to save some money on my build.
Firewolf137 months ago
I LOVE this idea for a system. Still working on gathering the parts though...
damionflynn (author)  Firewolf137 months ago
I found most of the lumber and such in my shed, but did buy quite a bit too. It is very possible, however, to get almost all the parts free from scrap less a few custom pieces like the plumbing through the wood on the siphon and the actual liner/pump

I hope you find all the pieces and do great :)
Toffy8 months ago
I think this is a great concept...good for you...and thank you and your Son for Sharing it.
damionflynn (author)  Toffy8 months ago
Thank you and you're welcome :)
cepterbi9 months ago
it looks great. tnx for sharing
JeffK62711 months ago
That's a sweet little system. I'm working on putting one together in Western NY State - I'll need either a greenhouse or a shed though, our winters get really cold and an indoor system is the only viable option.
damionflynn (author)  JeffK62711 months ago
That is awesome. I have been toying around with the the idea of greenhouse as well. I live on the MS Coast so we really only have two seasons - hot, and not so hot with the occasional freeze. I want to do a greenhouse-based system as well for tropical and subtropical plants.

Don't let the greenhouse hold you back though. Do a small system in your garage, basement, kitchen in front of a window, etc. I see small fish-tank-sized systems for indoors that are great for getting into it.

One note though on indoor systems - stay away from anything that needs pollinating. Most indoor systems stick to leafy greens (lettuce, spinach, etc) and herbs. Many of these you can actually float right on top of a fish tank :)

Good luck! It is a fun hobby.
Pocker0911 months ago
"use a filer/respirator though as PVC can release harmful chemicals"

Doesn't PVC do that even when not heated? I thought it activly leechs chemicals in to water?


An EU article on the topic
damionflynn (author)  Pocker0911 months ago
I did not see anything in those two articles that spoke particularly to PVC water pipe. That being said, I have seen where others have had the same concerns. My research on the matter in the past has led me to the decision to stay away from PVC that is made for wastewater but under normal circumstances, I do not feel that most PVC is a threat for a few reasons.
1. It is, from my research, perfectly safe in its finished state. It does however give off harmful toxins when heated or burned and fumes should be avoided
2. PVC is fully pliable and considered safe up to 158 degrees. If it gets that hot, I am not going to be to worried about whether the PVC is leaching or not :)
3. The final reason I felt safe with it is that as a master gardener and a man dealing with plants all my life, I know how good plants are at filtering things.

You are welcome to make your own decision and I encourage you to do the research and make an informed decision. I, however, feel more confident in growing in PVC pipe than I do in buying most grocery store fruits/vegetables :)
adeimar11 months ago
I am a newb gardener let alone aquaponics, and even with these questions this ible was VERY informative and well done. Kudos and thanks to you for taking the time to share it.
OK a couple newbie questions.
1) Do you use a pump or something to get the water into the PVC pipes to distribute (since the water will be travelling up it seems you would have to.)?
2) I am not following the strawberry towers and how they work. Is there a way you could elaborate and maybe post a couple of closer pics to show how they work?
3) Do you start your plants from seedlings and just place them on top of the rocks? It seems that some plants would be very much worse for the wear with their roots just exposed to the sun like that.
damionflynn (author)  adeimar11 months ago
1. Yes, I have a very basic (sorry I do not remember the exact GPH) pump that came in the kit with the liner. It works great but would suffer if there were too much more rise (height) to the planting bed
2. I may be able to post additional photos later but in essence, there is a 1" pvc pipe above the towers with holes drilled above each tower. The water drips down them and coats the lava rock effectively keeping the roots with water and nutrients. Then that water is collected and ran back into the tank by the 4" pipe
3. I started most of these from seeds and put them all in at the same time. You just have to make sure that your roots will get water at the top of the cycle. A little sunlight is not going to bother the roots as long as they are staying moist

Thanks for the questions! :)
RushFan11 months ago
I love this. Well done!
Love it. I want something like this. Are you concerned about that much weight on the deck though? I will put mine on or in the ground because I don't have a deck but still at about 8 pounds per gallon of water you basically have a small vehicle on your deck.
damionflynn (author)  Marcaine Art1 year ago
I thought about that early on but then broke it down...
My tank (the heaviest part) is about 18" deep. That means that in 1 square foot, I have approximately 11.25 gallons of water (1 * 1.5(for 18") * 7.5). Now, multiply that by the weight of water (appx 8.33) and you get just under 94 pounds.

I built my deck with the help of a family member and I feel very confident in it's ability to withstand 94 pounds of pressure per square foot. Putting that into perspective, it is like having 8 men stand there. If my deck can't support that, I would rather find out when the fish tank collapses than when I am having a party :)

Oh for some reason I thought I saw you say it was 200 gallons. My mistake.
damionflynn (author)  Marcaine Art12 months ago
It is, more or less. but the weight is distributed. 200 gallons on one small spot would obviously be to heavy for the deck, but distributed across 14 sq ft is much more reasonable.

The math I showed above just shows the weight "per square foot", which is perfectly within the realm of what the deck can hold. I would not go much deeper though because the depth (or height, depending on how you look at it) of the water is the major contributing factor to the weight per square foot.

I definitely understand your original concern about the weight on the deck though because it was something I worried about too until I calculated how much would be resting per square foot - and that is when I realized that although my system weighs about the same as my car, the distribution of the weight makes it safe.
dana-dxb1 year ago
awesome job
damionflynn (author)  dana-dxb1 year ago
Thank you :)

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