Aquaponics = Fish + Plants = Interesting Fun

[gn83tm]

I’ve been tinkering with something for a couple of months now and it may be of interest to some here. It’s called aquaponics and is a combination of aquaculture (raising fish) and hydroponics (raising plants without soil). The key is the nitrification cycle: The fish give off waste (mainly ammonia), bacteria in the plant growing media break down those wastes into nitrites and then nitrates, the plants absorb the nitrates and other elements to grow, and the now clean water flows back to the fish. It can be a delicate thing to balance but once it’s running it can run very smoothly with little input.

I decided to set up a system in my shop which presented me with a few challenges. First off, I only heat it to 45-50F unless I’m out there working and that’s kind of low for fish or plant growth, or even survival. Second, there’s not much light in there so I have it in front of a mostly shaded window and am running supplemental lighting. The heat issue will change once warm weather comes back and I may then try to move the grow beds (or the whole system) outside, into the sun.

This is what I started with, a used IBC tote:

I cut the top 12” off, inverted it, and set it back on the remaining part. The top part is the grow bed (GB) and the lower part is the fish tank (FT). Here are a couple of more recent photos:




As you can see, I also added an old bathtub as a second grow bed. One of the governing ratios to maintain is that the GB volume should equal the FT volume if you want to stock fish to densities of 3-5 fish per gallon. I have 150-200 gallons of FT volume and about half that in GB volume.

The IBC GB is filled with lava pebbles and there is a standpipe in the middle to set the max water level (1-1.5” below the top of the media). A fountain pump in the fish tank fills the GB through the PVC pipe around the perimeter and it runs on a timer: 15 minutes on, 45 minutes off. The tub GB is filled with pea gravel and has a separate pump constantly flooding it to the correct level. The drain draws water off the bottom to promote good flow and routes back to the FT.

I am running two 500 watt heaters in the fish tank and currently have them set at 80F. There is a 4 outlet air pump with air stones keeping the FT water oxygenated. I also made a 12 volt back-up system (deep cycle battery, bilge pump, relay control) to kick on if the power goes out.

I have some plants going that I pulled out of the fall garden and have also planted some seeds directly into the GB media. On 1/10/13 I added the protein – 50 blue tilapia fingerlings. They are doing well and getting chubby. If thing go right they’ll be on my plate in about 9 months. Yellow perch or hybrid bluegill were my second choice but the tilapia won out for various reasons. I really only have enough room for about 25-30 fish so can stand to loose a few or I’ll chow down on some smaller ones when they’re ready. Here are the tilapia getting ready for their new home:


So far, it’s been a fun project. There is so much to learn about the fish, the plants, the nitrification cycle and making it all work together.

[nedyarb]

You lost me bro! But it looks like a fun project. Good luck.

[Shorty]

Looks like fun! I have thought about doing something similar.

Where did you source the Blue Talapia?

Will your power back up system keep the fish tank heaters running? Talapia start having "issues" when the water temps drop below 55 degrees.

[gn83tm]

I picked up the tilapia from White Brook Tilapia Farm near Smithville MO (2 bucks a pop). They are supposed to be able to survive down to 45F and that was one of the factors I considered. My back-up system doesn't run the heaters so that is a concern. However, there is a lot of thermal mass in the system - about 250 gallons of water and 20 cu-ft of stone - so that should help a little. It's a risk for a couple of months per year but I'm generally not gone for more than a day or two during that time either. I'll probably figure out 10 other ways to kill them before a power outage chills them

[Omaha]

That is wicked cool Terry! Keep us updated! Need to find time to come out and see it in person.

[gn83tm]

Anytime Josh, just let me know. I'll let you feed the fish.....and sweep the floor......and polish the boat......and clean the bathroom.....

[Omaha]

Anytime Josh, just let me know. I'll let you feed the fish.....and sweep the floor......and polish the boat......and clean the bathroom.....

Maybe let me know when you're caught up on all those other projects and I'll check my schedule.

[gn83tm]

Time for a little progress report and some photos. This system has been running pretty well and is a fun, interesting project. Starting a little more than 2 weeks ago, we have been harvesting about 3/4 of a grocery bag of lettuce and other greens every 4 days or so. Most things grow really well, and really fast, compared to a dirt garden. I have had a bit of a problem with aphids but some imported lady bugs and I are working to eradicate them. The tilapia have been growing well and absolutely attack the pellet feed when it's feeding time. They are a bit shy, but fun to watch. They're 3-5" long at this point.

Here are a few pictures taken on 24FEB13:

[holdemplyer]

Looks like things are going pretty good, keep the updates coming. This is very interesting indeed.

[gn83tm]

Quick update with a few more photos.

Happy fish:


Not so happy fish:


Happy plants:


Happy lady bugs - making more aphid killers

[holdemplyer]

Not so happy fish:

No, I do NOT want a breath mint, I DO want back in the water though thank you very much....

Terry, thanks for the update, looks like thing are going decent.

[Phazedoubt]

This is very cool terry I just have a couple of questions. What is the cost of running this setup? Does it pay to do it or is it just something to do for an interesting project/hobby? Are you growing anything besides salad greens?

Gary

[gn83tm]

Gary,
I don't know if it pays or not but I know I've had hobbies that took a lot more money. Running costs are mainly electricity and a little fish food. I'm doing this indoors so I need supplemental lighting - currently using 720 watts for 12-16 hrs/day. There are 2 pumps running constantly pulling 26 watts each. Since I'm raising tilapia and my shop is only heated to <50 degrees in the winter, I have two 500 watt heaters going. They probably run about 1/2 the time and any heat loss from the system is going back into the shop so it isn't really an AP expense. Based on all that, I think the electricity costs me about $2.20/day.

I bought $40 of different fish feeds with the fish and that should get me close to getting them grown out. Minor input costs would be for seeds, a dash of liquid seaweed every so often, $20 for lady bugs to control aphids and white flies, 4 gallons of top-off water per day, and water testing supplies.

The system probably cost me a bit under $500 to build, including a $200 metal halide grow light. I probably spent about $100 on gravel buying it a bag at a time from Home Depot but I probably would have paid a lot less at a bulk supplier.

People grow about everything in these systems, other than maybe some of the root crops. I did grow radishes and I've seen carrots grown. I've seen folks growing sweet corn, tomatoes, melons, peppers, peas, beans, cucumbers, strawberries, flowers, etc. I've stuck mainly with greens and herbs since we eat a lot of them and they are easy and fast to grow. I'm trying to start some peas and peppers now also.

Whether or not it pays for itself remains to be seen. I'm doing it because it's interesting and fun. Also because it's nice to have fresh food all winter long without paying a lot of money at the store for something shipped 1500 miles by truck, and grown under questionable circumstances. That seems a bit silly to me.

Hope that answers your question but if not, let me know.

[Phazedoubt]

Thanks terry that is a great explanation. I've always wanted a greenhouse to grow fresh veggies all year and this looks like a cool little deal that would be interesting to try to incorporate into a greenhouse setup.

[gn83tm]

I'm dreaming about building a greenhouse to do this - someday.
I've seen where people are doing this in garages, basements, and everywhere else. It's a big deal in Australia and most systems are in backyards there.

[gn83tm]

A couple of weeks ago I started another, smaller system in the house. This one is mainly to provide kitchen herbs. It's built with a pvc fence post from Menards that I cut slots in, heated up with a heat gun, and formed pockets for the plants. The fish tank is an 18 gallon feed tub from TSC. I build a stainless base for the post to sit on and the plumbing runs up through the center of it. It is filled with an expanded clay media.

I tossed a couple of my daughters beta fish in there and one tilapia from the other system. The next morning I couldn't find the tilapia. Turns out he must have jumped out (or the betas threw him out) and was laying on the floor about 5 feet away. Lesson learned, he was replaced by 3 fantail goldfish to provide the plant nourishment.

The converting bacteria are still getting established in the media so the plants are struggling a bit - but we'll get there.

[holdemplyer]

Now that is very cool, and something my wife might possibly allow....

Thanks for sharing this adventure Terry, I get excited when I see there has been a new post!

[tmmiller72]

Now on the post do you still need to feed the fish? (Ignore I started reading other sites and answered my question)

that is really cool did you get the plans from a certain site?

[gn83tm]

Now on the post do you still need to feed the fish?

that is really cool did you get the plans from a certain site?

Yes, you need to feed the fish, otherwise they don't put out any nutrients Believe it or not, I'm probably overstocked on fish for the amount of media and plants in the system. The 3 goldies and 2 betas are putting out enough that I'm running a bit high on nitrates. It's kind of a welcome problem though since I just pull a gallon or so out every day and water house plants and garden starts with it. I then just top off the tank. Plants love the high nitrate water.

No plans really. I just kind of made it up as I went. The only thing really special is the base. I laser cut a 1/2" thick stainless circle at work and welded on a section of 3" stainless pipe that had opposite quadrants cut out of the lower 8". This provided support for the post, a place for the pump, and the the supply tubing runs up the middle. I bolted a 1" thick plastic (UHMW) block inside the post and that rests on the top of the pipe. It sets the height and holds the media up. The tubing goes through a hole in the center.


A shot looking downward from the first plant pocket:


I drilled and flared some 1/4" drain holes just above the block. The idea was that they would stream water out in nice streams that would help to aerate the water. In actuality, there isn't enough flow to do that and the water just runs down the post. At some point I'll shorten the stainless pipe so the drain holes are below water level.

The plant pockets were made by cutting slots at 6" intervals on opposite sides of the post. I heated the area with a heat gun and when it became pliable I used a long, tapered transmission funnel to shape the pockets. The material doesn't really stretch but it can easily be re-shaped when the temp is just right. Too hot and you'll blister the finish.



It was a fun project and I have some ideas for improvements. The stainless base is a big hurdle but I have an idea to make it a lot simpler and cheaper. Not including the base, I have about $50 in the basic unit. To make it more functional, I also spent a few bucks on an aquarium heater ($30), air pump ($15), and timer ($6).

Let me know if you have any more questions.

[mgbrin]

Thanks for posting. One quick question...I know almost everyone does these with Tilapia (which I don't care for), but I do believe I've heard of people doing them with yellow perch (which I do). It sounds like you've done the research....did you consider other fish?