The water fall is kind of a pain in the ass. I have a lot of trouble with it leaking off the left side of the front. I've been trying to fix it with some plastic model contour putty so it won't do that. As far as cleaning it, I put Biotize waste degrader made by Exo Terra in the water, and it seems to keep the water clean. My cham doesn't drink out of it, so it's not a big deal for me if the water isn't totally clean. The light is on the side because I built the cage to slide into my entertainment center where there would normally be a couple of shelves and after I slid it in, I found there was nothing to clip the lamp to, so I drove a nail into the top of the entertainment center and just hung the light on it so it would rest on the side of the cage where there are branches leading to it. There is a flourecent UV bulb across the top in the front.