My pond will fall far short of yours ! I will start a thread on it as soon as my work demands die down a bit. Will let you know. My 3 foot tank only contains the plants at this stage. I dont really do any maintenance on it. I wanted to let the plants get established on their own. There is no filter or air stone in this tank. The tank sits just out of reach of direct sunlight but does receive a lot of diffuse light throughout the day. I dont measure temperature in the tank and only do top up's for evaporation losses. It's just an experiment that I started on an old scratched tank for fun. Nothing close to the majesty of yours. It is standing right beside my pond. The initial idea was to use the pond as a sump and then have various out door tanks with a single pump supplying them. The water return would be through a pvc auto-siphon. But I havent gotten that far yet.