I have a 55g with gravel and I'd like to change over to sand I have an under gravel filter and a Penguin Power Filter 350B the combination seems to keep the fish happy and happy fish in a clear tank makes for many hours of starring at the tank. I think sand looks so much more classy and would like to switch over but I assume if I had to remove that under gravel filter as well it'll be a task not worth the work.