The only thing I was considering is a floating bed of duckweed because I heard they're one of the only plants that can convert ammonia rather then nitrates exclusively. I thought it would help as a buffer to reduce my novice ability at this point.
Not a bad idea. One thing I'm usually told with duckweed, though, is that once you have it in a tank it's nearly impossible to get rid of it, so you may want to keep that in mind. IF you want to go with purist aquaponics, The thing to do would be to let the tank "cure" like you would with a normal fishtank so that the ammonia is not too high when you add fish. then add a few fish at a time so the bacteria colony can keep up with the rising bio load. That's why I chose to put some mollies in my setup - the process of conception, pregnancy, and growth of fry is a great way to have the population rise (and the bioload slowly rise with it) without much effort. If you're going to go with food fish, though, start with a few tilapia, then slowly add more (like maybe add 2 when you harvest one or something along those lines? I'm guessing here as I've never raised tilapia or any kind of people-food fish and don't know their requirements.)
I understand the canister filter builds up the good bacteria that breaks down the nitrites into nitrates which is adequate for the plants to grow but will the filter prevent nitrates from passing on into the grow beds? I was under the impression for a true aquaponics system there is no filter and the pump just feeds the water into the grow beds where the plants are the filer by soaking up the nitrates.
I can't think of any reason the nitrates would stay in the filter, unless you're using nitra-zorb or some nitrate-trapping product. My Canister filters have Bio-rings and bio-balls to grow the bacteria and some cotton batting like you'd find in a quilting store to trap large particles of plant matter and fish waste. That way the large particles break down in the canister where most of the bacteria is there to turn them into nitrates which plass through the canister to the plants. I also get more bacteria growth area because the bacteria grows on the batting as well.
This is the way I was going to do it but I also found out CPVC rather then PVC is the way to go so you don't leak PCBs into your fish tank and food supply. Another option is polyethylene tubing but it's very costly.
I hadn't heard of PVC leaking any PCBs. What is PCB anyway?
The raft Idea I was thinking about for the duckweed I mentioned earlier. As far as a method, at first I was thinking of a continuous flow for it's simplicity but as I researched it I found it's inferior to a flood and drain setup. I'm thinking of doing a flood and drain on a timer and possibly a nutramist or ultrasonic fogger on a timer alternating. It will probably take some tweaking but most likely ideal.
Yeah, when I did continuous flow I only got things to sprout, then they stopped growing. they didn't die, but they didn't grow much either. Of course, I was tweaking my setup constantly and that can't have helped much either.
Now that I've got the leaks stopped, I have my canister filter that pumps water to the grow bed on a timer. It goes on for the first half of each hour and off for the last half and I'm seeing some growth, though nothing miracle like you see in the aquaponics instructional videos on youtube. I think most of the videos and info I've seen on it have the water run 1-4 times an hour for under 5 minutes at a time. In my mind, the more contact with the nutrients in the water, the better (as long as the plant is getting enough oxygen, of course) so I think I'll stay with my half and half regimen for a while and see how things turn out.
The other thing that may be affecting my growth is that I live in Utah. I'm trying to grow summer crops (peppers, green onions, lettuce, peas) in the winter and can't afford to keep my house the 80 or 90 degrees that these plants like. I'm hoping keeping the water at 82-84 degrees will be good enough there. Our house is usually between 65 and 70 so the plants won't freeze, but they're not as warm as they like either.
I bought a 160 gallon outdoor plastic koi pond. I'll probably fill it to 100 gal. I'm building this completely indoors in an unfinished basement. Concrete floor and cleanspec plastic wrap walls. There's also 3 sump pumps and 2 pits in case of emergency.
I will probably have to run a dehumidifier to keep moisture out of the air since it's inside the home but I don't want to dry out the plants leaves. Maybe a fogger within the grow bed foliar feeding in the dry air is a good option.
Unless you're trying to grow aquatic plants emersed, I Wouldn't worry too much about creating humidity. Most plants that are successfully grown aquaponically can also be grown in the dirt with dry air. I think as long as their roots don't starve or dry out completely, they'll be fine.
Dimensions of the basement are 30' x 40'. I will most likely have 3 rails x 30' of 6" CPVC. 3.5" Net pots spaced 12" on center. I'm sort of thinking 3 sets of 4 lights - 4' HO fluorescent lights for total of 12 lights. Obviously in the the middle of each 10ft section of the 30ft grow bed. So each 10ft section is going to receive 20,000+ lumens at the cost of just over 600 watts. I should be able to grow anything from lettuce to fruits with a mix of 6500k and 3000k lights.
What do you mean on center? I assume you mean that you're making sure the pots are in the middle of the PVC pipe? sounds like a nice setup to me. I'm jealous of the space and worry free setup you have. Every time my setup leaked, it ended up on a floor covered in 10+ year old carpet.
Will you slope the pipes as well so that the water is gravity-fed or will you pump it back to the fish tank?
I'm thinking this is going to take a lot of nitrates but by your formula of 1 gallon of water per 1 foot of grow bed, that's 160 gal and 90' of grow bed only 6" in diameter. That's why I was thinking I have to fill it to 100 gallons rather then the designed 160.
I wasn't really sure on the estimate I gave you, but I found at AquaponicsHQ
that depending on stocking density, it sounds like systems can do 1:1 to 1:4 ratios (cubic feet of water to cubic feet of growing media).
Any suggestions or thoughts? What about recommendations for pump output? How frequently would you suggest the 100 gallon fish tank should be turned over. 3 times per hour? More?
I haven't done a lot of research on pump output. I think it's all in keeping within the head (distance from the top of the pump/canister filter to the height of water you want to pump) requirements. I have an XP3 that pumps in a head of about 3 feet. Pump rate will also determine drainage. In my case, 4 1/2" PVC pipes did not provide enough drainage from the grow bed but a 1" pipe and a 1 1/4" pipe with another 1" pipe for backup does provide enough drainage.
With turnover, I think it's all just a matter of experimentation to find out what you like best. you don't want the water washing all your seeds to the same spot so they fight for growing space, but you want to make sure you can get the water to them.
Maybe the best thing is to find some kid of pump that will turn over your water once or twice an hour with a maximum head that matches the distance you're pumping to the top of your grow bed(s)? Again, I have only very little experience with this and am just guessing based on that.
Are you able to get pics of your setup as you're constructing it?