Well, with the new, young discus and their being feed five/six times a day, my tank clean up at the end of the day is not going good. THe sand is turning brown ever night from both the ultra fine food waste I can't remove and, of course, the massive waste from the fish. The good news is my water nitrate remains below 1 ppm (measures from 0.4 - 0.8 ppm and the phosphates hover around 2 ppm.) Since I can only care for them at night, I will have to either remove the sand or return to service my reverse flow UGF. These units kept my sand pristine - the up flowing water not only helped me remove all food particles (even very small) by vacuuming (the particles cannot sink into the sand) but encourage a small bacteria culture to grow in the top layer that converts waste into nitrates (which my active nitrate filters easily remove.)

I had removed these to save electricity and since my nitrate filters allowed me to really go easy on water changes (my tap is high in nitrates so W/C do not help - my nitrate filters do convert this into clean water but that takes a day; hence, I do only bi-weekly water changes.)

I wil lsay this, while sand isn't at all needed (it is impossible to have plants with nitrates so low) I just don't really want to remove it ... maybe in a few months I'll give up and bite the bullet relative to sand.

For now, with the vast amount of fish waste that these little critters produce thanks to their eating enough food to feed a small army, and since the sand will provide a good culture media for bacteria to clean the sand (again, nitrates are not an issue due to my active systems) I guess I'll continue with the sand in the tank and let the UGF (along with my canister, algae scrubber and nitrate removal unit from hell) continue to do their jobs - will be an interesting experiment to see if it works as well as it did a while ago when I first developed the idea. Of course, I didn't have the nitrate filters at that time.