Backyard Aquaponics
A place to discuss aquaponics

That PDF is "ECONOMIC BENEFITS OF INTEGRATING A HYDROPONIC-LETTUCE SYSTEM INTO A BARRAMUNDI FISH PRODUCTION SYSTEM."
(I dislike clicking on unidentified links, so this is to help anyone else with that phobia... )

I've only managed to print it out so far. Haven't had a chance to read it yet but am about to sit diwn with a cuppa so I might read it now.

The first thing I noted was that 550m2 of growing area only uses 5% of the available N and P. I guess that includes walkways and stuff were we would actually count growung area as distinct grim area in which things are grown.

The second was the small number of benefits from integration. Since they are essentially two systems run side by side there are no capital benefits of integration. Similarly there are no electricity savings.

And still lots of waste. The water was fed through NFT Channels once and then disposed of.

That is more bioremediation of aquaculture effluent rather than AP as most people would know it...

I don't think it is very good AP or at least not realising the potential of the concept but I'd still call it AP.

Third thing I noticed was the sensitivity of the model. How easy would it be for barra prices to drop below $12/kg and lettuce below $0.5/head?

Sorry, should have titled it proper.

It is not AP because the water does not return to the fish tank.

I think the system would have great potential if the lettuce production matched the fish waste output?

I wouldn't think so, it's still AP, just because it's not recirculating doesn't mean it's not AP, just AP many people wouldn't do.. I think that might be why this topic was started..

viewtopic.php?f=13&t=9688

should we start another thread?

Ahh, was wondering why Stuart started tht thread - makes sense now

Yeah I was trying to keep the two discussions seperate. Probably foolhardy but oh well.

wtf is this doing here on this thread