Impressive
I have a gravel filter with some special bacteria-grow pellets on the bottom of it, and a UV filter on top. I get weed-type algae, but the water itself stays quite clear. I planted a cattail last summer in a little tub on the bottom (partly so those dragonfly nymphs had something to climb up) and a raccoon knocked the hell out of it and the lily pad. All I see so far is dirt in the underwater pots this year, and I'm hoping these plants are half as robust as they're supposed to be. I swear about a dozen of those damn raccoons get in there and do Esther Williams routines. The whole frigging pond is only about seven feet across.