meeee wrote:

Aquaculture?


Sort of but more complicated..... a hydroponic system and aquaculture system
all linked, so that the fish water flowed through the hydroponic gravel, the
plants removed the poo etc then the now-purified water was pumped back in to
the fish. There was beneficial bacteria involved, in the gravel I believe,
and he was working on growing his own pond weed to use as fish food, so that
it would be completely self sufficient. DH got all inspired and wants to do
it now


Hmm, yes it does sound very complicated but it sounds very efficient -
if it all ran as it should. I suppose then the poo-ridden extra waste
could be used again to grow more even more plants. More fish... a real
cycle alright.