lol, no they are all in the same tank, but it's funny how they seem to stick to their own sides. Although the goldfish have just been kinda all grouping up on the one side of the tank for several weeks now. Not sure about that if anybody knows? Yes, been trying to clean the tank and replenish 20% water change every week, or at least every two cause it starts getting a little cloudy. I bought an oversize filter to extend cleanings, and this was the first time in 3 months so you can imagine how gross it was! Yuk! I'm using a Fluval, sounds like a recommendation to stay away from undergravel, thanks!