Backyard Aquaponics
A place to discuss aquaponics

So I'm planning on upgrading/redesigning my system to expand, reduce siphons/drains and add a DWC. Above you can see my sketch so far. It will be a CHIFT PIST setup. I would like to keep about 200 tilapia in each FT. This system is to feed my family of 5 and also share with other family and friends to spread the AP fever.

The grow beds would be built out of wood and painted sealed or lined in plastic.

I will build a trellis of some sort over both GB. Sump will be a 250 gallon tote.

I'm not sure what size media grow bed and dwc beds I should go with (see above picture for details). I'd like to go with 288 inches wide. Need some guidance here though.

Let me know what you think.

Thanks

Luis

This is a tough question to answer because everyone has different tastes and so they need a different amount of produce and different types as well

If you want to grow all the veggies a family of five could eat then you aren't looking at a big enough size. On the other hand, it's a different story if you just want to supplement with your own produce. Some things like fruit tree's, berries, potatoes, corn ... are best left out of the system for a variety of reasons so save some space for these elsewhere (we usually try them in AP anyway )

Are the 2 250 gallon FT with with 2-400 tilapia enough to feed the larger grow beds?

I will add valves and extra pipping to control flows and isolate filters for cleaning.

We grow our big trees in the earth. Avocado, lemon, lime, grapefruit, mango.

200 is way too many fish for a 250 gallon ft..
base fish load on filtration

The grow beds will be 300-1000 gallons each. Is a 1000 gallon media bed not have sufficient surface area for the nitrification in addition to the surface area of the 300-1000 gallon DWC, 50 gallon net tank, and 50 gallon cloth tank?

Wife and I discussed the sizing of the beds and might go 8 foot wide instead of 4 since we can reach about 4 feet from both sides. If so, we would double the volumes above.



What do you recommend? How many tilapia per gallon of media is good?

How far across you can reach will depend on the height of the beds, be certain to take this into account if you haven't already. Eight feet wide is very wide for a bed.

Sounds like you really want to grow fish. During some basil and tilapia trials, the University of the Virgin Islands, which has vastly more experience than any of us here, didn't even stock at your lower level. They had 77 Nile Tilapia per cubic meter (around 264 US gallons) and in another tank grew Red Tilapia at 154 fish per cubic meter - http://www.uvi.edu/files/documents/Research_and_Public_Service/AES/Aquaculture/Tilapia_and_Basil.pdf. Keep in mind this is in tanks designed for fish, with blowers for aeration and lots of filtration.

I think Keith's stocking levels below are more realistic for most people.

1000 gallons of wet media would be sufficient for about 250 to 300 lbs of grown out fish..

but your fish tank still has to have room for fish..tightly packed i've seen 1fish/3 gallons, but i wouldn't be comfortable with that (i might go with 1/5 gallons with really good filtration and oxygen, and a backup.. what size do you plan to grow the fish out to? (i've had tilapia up to 3lbs)
do you plan on breeding them? that won't be possible with that many fish in a tank, but you could set up "breeder" tanks..

re bed size.. as noted, too big is hard to manage/reach across for harvesting/planting/monitoring

Scotty,

Thanks for the link. I need to reread the uvi system details.

As for bed width, what's a good bed height to the top of bed for 8 foot wide? Currently the barrels I use are at 6" below my waist and can easily reach the otherside if its not too dense in high growing plants. I'd like to stick with 4' or 8' for ease of contructing.

The main purpose my system is to grow safe, healthy eatable food. So that includes fish. I'll read the UVI link to get a better idea on amount of fish/feed is needed for plant growth. My 200-400 goal does seem like a lot of fish to eat though.


Thanks for the reply. Keep it coming.

+1 on 8ft being too wide for a MB bed. It would be fine until it was fully planted. Then you would have to contend with reaching over and through all the plants on the outside to even reach the middle. Now if it were a DWC then no problem. As long as you plan to pull the rafts fro planting, harvesting, and cleaning. Which many do anyway.

Keith,

Point taken for sure. I'll back down my fish number to 100. And see how that goes to harvest. I'll put 50 in each tank and rotate the harvest. I have a breeder tank now with 4 females and 1 male. They breed like crazy.

My next question is how big of a drain should I put on the DWC and MGB? I currently flood and drain my barrels with 3/4". They empty in a couple min. Now multiply that by 8. There is always a siphon not working properly so I'm leaning to constant flood but would like to keep the siphon option available in case I change my mind. Is a 2" drain sufficient for a 1000 gallon drain.

In a perfect world, my pump will run at 1200gph at 5' head. So I guess I'll split that in half and 600 gallons will go to the DWC and 600 to MGB.

Does this sound ok?

Thank you for your input. I sincerely apreciate it.

That means you are splitting the flow after your mechanical filtration, I hope.

Correct. Like the picture in my first post above.

Measured my barrel grow bed, it's 3' deep. I simulated a 4' grow bed and was not able to reach the far end. So 8' is out the window. Sticking with the original plan of 4'.

I think that's a wise choice

As far as splitting the flow, if I remember right you want to turn over the DWC at least once every four hours and up to once every hour. So your DWC bed volume will matter in calculating this flow.

Scotty,

Now for the two drains. Will 2" drains be ok on each GB be sufficient?