I have a 90 gallon open top, my lighting system has legs that mount on the frame of the tank. I lose about 1- 1/12 gallons a day to evaporation. As far as doing the vaccum, sure cant hurt to get any detrius matter out. Dont do the whole bottom at once during that water change, just do half. Then your next water change, do the other half. Cuts down on removing to much benificial bacteria all at one time. |