Backyard Aquaponics
A place to discuss aquaponics

Ok, the people selling the plans for their take on a uvi system claims to produce 150-250 lbs of vegetables per month and 20 lbs of fish. It has 8 tables and uses 67 kW hours of power per month.

So, what type of veggies can grow 150+ pounds per month and how exactly are they managing 20 pounds of fish per month? Is this the whole fish weight?

If those figures are true and the weights eatable, then that pretty stinking good!

Any thoughts? Can this system be that good?

I am looking at adding this to my system next year.

Who is it Dandi???

I suspect that the weights are estimates based on growing space and best case situations. If they are actual weights of product pulled out of the system, I'm sure it is definitely the whole weight of the fish, not fillets or anything like that.

I could easily pull 20 lb of catfish out of my system in a month but I don't think I could do it every month of the year at this stage in my learning.

I'm not as sure about pulling huge amounts of veggies from a system but that is just because I'm still working on getting the right balance in my system and I don't know how to weigh what the rodents have stolen. Certain types of plants will provide huge huge weights of yield compared to others. Things like squash and zucchini can provide heavy harvests is short time while some tomato types will also provide heavy yields.

I do have a bit of trouble seeing 150-250 lb of veggies per month every month, but perhaps the biggest harvest of the year being in one month could be somewhere close to that.

Thats kind of what I was thinking TCL.

Rupe its these ppl, http://www.friendlyaquaponics.com/doitmyself.html

However, my hydroponic test on DWC proved to me that it was superior to flood and drain for banana pepper production. At least three time larger plants and number of peppers over my flood and drain test. However, having to tie everything up could kind of suck.

The secret ingredient is Hawaii!

That is a pretty good secret ingredient

And the figures quoted vary from site to site, media interview to media release...

And are somewhat "projections".... the farm has only been operating for about 12 months... and viably, constantly for about 3-4 months...

They introduced themselves here... and on other forums... have a "grand" vision...

A 32 raft system equals 1024 sq. ft. If you set this up, conveyor style in a cycle of four weeks, starting with one week old seedlings and harvesting every week, you're looking at harvesting 8 rafts per week.
The UVI system I know well. UVI has 84 heads of lettuce per raft, each head weighing 5.3 oz. at harvest, so one raft of lettuce would weigh 27.825 lbs. or .869 lbs. per sq. ft. UVI has 49 lettuce harvests per year.
As far as costs of the operating system, the researchers have admitted that if they had pond walls that shared with the next pond, instead of creating individual ponds, the system could have been made with lower costs. Dolphin commerical water pumps use roughly 1/3 hp and move large amounts of water so purchasing an energy efficient pump to start with would also save on operational costs in the long run.
Pump Dolphin 1/3 HP max 22' head 5600/4700 GPH saltwater applications www.aquariumsuppliesplus.com/


UVI System Design
Tanks 4- 10 ft Dia., Height:4 ft, 2,060 gal each Total 8,240
Clarifiers: 2- 6 ft Dia , Height : 4 ft, Depth of cone: 3.6 ft, 1,000 gal ea Total 2,000
Filter and degassing tanks: 2- 6ft x 2.5 ft x 2 ft deep, Water volume:185 gal Total 370
Hydroponic tanks: Length: 6- 100 ft x 4 ft x 16 in. deep, connected in pairs for 200 ft. runs 3,000 gal. Ea.
Total Water 18,000 gallons

Growing area: 2,304 ft2 (6-96x4) 12- 4’x8’ rafts ea. 72 rafts total
Sump: 1- Diameter: 4 ft, Height: 3 ft, Water volume: 160 Base addition tank: 1- Diameter: 2 ft, Height: 3 ft, Water volume: 50
Total system water volume: 29,375 gallons

Pond to Tank Ratio: The commercial scale unit at UVI has a ratio of 7.3:1.
The total plant growing area is 2,304 ft2 and the total fish-rearing surface area is 314 ft2.
Flow rate: 100 GPM- water retention time in fish tanks is 82 min. or a total flow of 24 gal per min per tank but are adjusted for the tank closet to harvest at 60 min. and the smallest fish tank at 120 min. http://cpws.cqu.edu.au/FCWViewer/getFile.do?id=25105
Water pump: 1⁄2 hp
Blowers: 11⁄2 hp (fish) and 1 hp (plants)
Total land area: 1⁄8 acre

Pipe sizes
Pump to rearing tanks: 3 in
Rearing tanks to clarifier: 4 in
Clarifiers to filter tanks: 4 in
Between filter tanks: 6 in
Filter tank to degassing tank: 4 in
Degassing to hydroponic ponds: 6 in
Between hydroponic ponds: 6 in
Hydroponic ponds to sump: 6 in
Sump to pump: 3 in
Pipe to base addition tank 0.75 in
Base addition tank to sump: 1.25 in
SRAC Publication No. 454- Recirculating Aquaculture Tank Production Systems: Aquaponics—Integrating Fish and Plant Culture
http://www.ca.uky.edu/wkrec/454fs.PDF


Another factor to consider in determining the optimum feeding rate ratio is the total water volume of the system, which affects nutrient concentrations. In raft hydroponics, approximately 75 percent of the system water volume is in the hydroponic component, whereas gravel beds and NFT troughs contain minor amounts of system water. Theoretically, in systems producing the same quantity of fish and plants, a daily feeding rate of 100 g/m2 would produce total nutrient concentrations nearly four times higher in gravel and NFT systems (e.g., 1,600 mg/L) than in raft systems (e.g., 400 mg/L), but total nutrient mass in the systems would be the same. Nutrient concentrations outside acceptable ranges affect plant growth. Therefore, the optimum design ratio varies with the type of hydroponic component. Gravel and NFT systems should have a feeding rate ratio that is approximately 25 percent of the recommended ratio for raft hydroponics.
SRAC Publication No. 454- Recirculating Aquaculture Tank Production Systems: Aquaponics—Integrating Fish and Plant Culture
This means that stocking ratios are higher in raft systems.
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Very nice summary of UVI raft style aquaponics.... thanks Angie...

Very good info!

Its also interesting that plans are being sold for a system that has only had a few months operation. Hardly a proven system.

As far a veggie production I guess that is if you produce fast growing greens like lettuce and that the harvest weight will be far less with other crops. Lettuce is not going to "cut it" for me as it has little nutritional value.

None the less, I think I will try adding raft test table to my sum and see what happens. My climate is not tropical so a steady rotation of the same fish and veggies is not going to happen either..

Thank you all for the info! This helps me make more informed choices.