My basic system

[samtheman]

This is my 600 gallon pond, I have a 30 gallon mechanic and biofilter, I set up a timed flood and drain system on a 7' pvc post with 3" netted baskets with herbs and strawberries. I installed a 8' x 12' sunscreen to protect it from falling leaves. As I get more experience on this I will switch to blue tilapias, so I am trying to find a place near Orlando where I can get some tilapias for my pond. I am barely getting into aquaponics so I am open to any suggestions you may have....

[badflash]

Depending on how many fish you have, you probably need a lot more plants. Typically there is a 2:1 plant surface area to fish, but of cours it depends on the fish and the plants.

[Oldandfound1]

Wow, what a good looking system Samtheman. With great potential for AP. You have great council nearby already. As near as I can tell I am the only person here from Washington State currently posting or who will admit being an AP'er. Have had great guidance here at DIY when I asked, and otherwise read and re-read.
Dennis
Oldandfound1

[davidstcldfl]

Nice samtheman...

[samtheman]

thanks guys...I appreciate the comments
@Badflash - I am a little confused as to how many plants I can have without affecting my setup, a ratio of 2:1 plant surface area to fish sounds like a good idea for me to go by..thanks

[badflash]

If you have too many plants it won't hurt the fish, just make the plants sickly. How many pound of fish per gallon do you have? Alternately, check the nitrate level. If it continues to rise you need more plants.

[Brier]

A reasonable stocking rate per gallon would be somewhere around 1/4 pound of fish. This is conservative in the aquaculture industry, and can be achieved with low cost equipment. So 150 pounds of fish would be a nice number to shoot for. If your target weight is 1.5 pounds, you might want to stock about 110-120 fish, to account for any death loss. Next you need to size your filtration, use 25 square feet of surface area per pound of fish. Lets take your 30 gallon filter out of the equation, it really is doing much less than you might think. Pea gravel is about 95 square feet of surface area per cubic foot of volume. So to provide biofiltration for 150 pounds of fish, you need roughly 40 cubic feet of pea gravel grow media. So, to make this easy, imagine a 4 foot by 10 foot growbed with one foot depth of pea gravel. That is the overall potential of your current unit, give or take. I would always error on the conservative side. I am figuring this from a purely aquaculture standpoint, which does not account for root mass, adding additional square footage for bacteria to grow on. So this should be a fairly conservative estimate. Your other variables are flow, and aeration. Your growbed will function more efficiently as a biofilter if the flow rate is reasonably high. I have not seen any studies on growbeds specifically, but it would seem that if you flood your growbed 20 times per day, that you will get better biofiltration than if it only floods 6 times per day. The higher flow will provide a constant source of nutrients for your nitrifying bacteria, and allow for a heavier colonization. Higher flow will also go a log way for adding extra O2, as your growbeds will act as an aerator, and a degassing column. Of course, supplemental aeration is very important at these stocking densities, and a good air pump is a must. If your water flow suffers from clogging, or fails, your aerator will help pick up the slack. Take this all with a grain of salt, as I am really an aquaculturist, moonlighting as a aquaponicist(?). The principles should still hold true. Good luck, and BTW, you have a very nice setup, my wife even commented on the aesthetics.

[samtheman]

Wow you guys are awesome!
The info I have gather from this forum in 2 days is priceless, I have alot to learn and make time to digest all this info
@badflash and @Brier - thank you for your wisdom, I will be happy to learn half of what you guys know....

[jackalope]

Nice

[samtheman]

Ok...As you guys know I am a rookie at this... I am not sure if I understand this correctly but according to the size of my pond (600 gallons). Is my 30 gallon bio-filter too small for it? Should I go bigger, maybe a 55 gallon barrel? Can I have like 15 or 20 healthy blue tilapias in my pond with my current system? Should I go with a different filter setup all together?