Backyard Aquaponics
A place to discuss aquaponics

Hello everyone, I am in the final planning stages of a new greenhouse for my first owned home in wet London England. The building is to be half greenhouse and half a small workshop for both bicycles (I am a mechanic) and for the renovation of the house. The nature of the garden means that the greenhouse can only face east to west - London terraced houses have long thin gardens. The greenhouse side will be 2m wide (south to north) and 3.6m deep (east to west). To the west side is the workshop which is slightly less deep at 3.2m. The greenhouse would contain sub-floor sump tanks of 400litres (I guess that's about 90 gallons if my conversion memory is correct) and 200 litres to balance a tank of 825 litres (180ish gallons) which would be shielded from the sun by a stud wall and recessed into the ground by about 50cm (1 1/2 feet). 3, 80 litre grow beds, a rack of 4ft strawberry towers and 1 or 2 80 litre raft beds would be the starting set-up, although there is some room to add another bed/raft and move the towers.

Ideally, the system would be off grid, apart from emergencies, using 2 x 100w solar panels on the roof facing east (not ideal but that is what is available). I would like to power two pumps in each sump, one for primary use and one as an emergency backup with the float switches set to a slightly lower depth. In addition, I would like to run an aerator in the fish tank with a battery backup inside although I hope the design will mean this is added redundancy.

Although I am well used to building work and I don't have any real worries about the structure, and whilst fairly confident with the both the fish and the plants (I wasn't born in the city) I am new to the electrics side of things. Whilst I can get a good electrician to help me, I am struggling to work out a system which, in the event of a failure of batteries/Iceland ash cloud/2 weeks of very cloudy weather etc would be able to switch to the mains from the house without being prohibitively expensive.

Having used this forum and others to help me get this far, I joined up proper to try and get the benefit of more experienced off-gridding aquaponics members.

Welcome Tim! Even when the S doesn't HTF, you will find the journey into AP rewarding in itself.