I've had a bare bottom on my 75 gallon for some time. I've never used sand and decided I'd try it when Imagitarium black sand went on sale at Petco. I have to say I really like it, but now instead on doing a weekly larger water change vacuuming the nasties from the bare bottom much of which has collected under decorations I do a 5 gallon bucketful almost every night to suck up the poo of the day from the sand surface since it remains there and can't get underneath anything. I of course can't stick the siphon into the sand as one would do with gravel but I hover a few inches above it as I did with the bare bottom.