Some people don't, wook. The rule of thumb is that you can really only get 1 fish per 5 gallons or so. So in a medium-sized, non-commercial system (275 gallons is about as big as a backyard system can probably go) then you're only getting about 50-60 fish stocked, and they take about 9 months (6-12, depending on a lot of factors) to get "plate-sized". Some people say that that isn't worth the effort to kill (or just don't like tilapia) and put in ornamental fish like koi or goldfish or something, and never eat them.
I was really debating on growing koi fish. They actually can sell for big bucks; more than you can sell a tilapia for. As for density; I've worked in aquaculture for a while now. The 1 lbs per 5 gallon of water is a safe bet. As long as you have the plants, air and media beds to support higher density; you can grow at a rate of 1 lbs per 2 gallons of water. If you research tilapia; they actually like higher density areas.
Tilapia is the hardiest fish in aquaponics. That's why they are used so much. In my system, I'm using a lot of air stones and over building. I have a total of 1,000 gallons of water (from the fish tank, sumps, vertical grow towers, raft beds and media beds). Normally a 500 gallon per hour system is fine for this application. I am using a 1,200 GPH pump, so the cycling will be 3 times as fast. This will help keep the system clean; plus having many plants to absorb all the waste. I over built the air system as well. Normally, this system would only need 1,500 gph of compressed air. I added a total of 3,500 gph of air; plus our company manufactures an aquaculture amendment that increases the DO in water (decreasing the possibility of anaerobic locations in the system). Then adding "earth worms" to the media beds will help to avoid ammonia spikes because they consume most the solids that make it to the media beds.
Anytime brother! You have a place to stay and cool things to look at too! And I don't mean my wife you pervert!
Is there a graphic representation of the whole system (not necessarily yours, mags) somewhere? I find this stuff fascinating...
There are blue-prints, youtube animations of the way it cycles. Just use google! I have a few links for you to read up on, but the true understanding is when "you" investigate and find the knowledge yourself! http://aquaponics-system.com/176-500-gallon-aquaponics-system/ http://aquaponicseasy.com http://aquaponicseasy.com/ebb and flow aquaponics system.html This is the company I get my aquaponic supplies from. I am currently working with them in designing a siphon system to house fruit trees. http://theaquaponicsource.com
Pretty danged cool. Thanks, Mags, and good luck with it! If you ever figure out how to get beef out of one of those things, I'll move in next door...
That's really quite simple really. All you do is add the cattle and grow the vegetables they would require. Then you can feed the animals, much like we would feed ourselves. The advantage to the "greenhouse" system is a year round fresh meal for the cattle.
Just grow ornamental fish in the tank. The fish are the fertilizer for the plants. You don't have to grow the fish to eat.
I had a girl insist she had met me at a vegetarian club meeting, but I swear I've never seen herbivore...
I am a HUGE "red meat" fan. I can eat fish, but it just doesn't satisfy me. I do love vegetables though. I would say if you grow vegetables, I bet you eat more. There is something very rewarding when you are growing your own food.
So I decided to get a Hanna (pH, PPM and Temp) controller. I hung it on the back of the greenhouse, so it is easy to see. I also installed a de-chlorinator and sediment removal water filter and placed a "float valve" going into the sump. This will make sure my water levels never drop below the pump and burn it out. It's important to make sure no water going into the tank is chlorinated.
