For fun I collected all the spare fresh water bits and bobs that I had left over and set up my first saltwater tank at the office. It's a twenty gallon with an AC150 without media, two power heads with about 15 lbs of live rock and about 10 lbs of base rock. Lighting is an inadequate single bulb. Substrate is hardware store play sand. After having the tank run for about a month and watched a diatomaceous algae outbreak burn itself out I added about 5 small blue-legged crabs, a brittle star fish and a 5 snails. Everyone seems to be doing fine. The little clean up crew seem to be doing well and the few tests I have run suggest I am ready to add a fish or two. However, my family and I are going away for a holiday in about six weeks time and I don't want to add any fish before I can keep a close eye on them. So here is my stupid question: do I need to feed my live rock and cleaning crew to keep the tank habitable for when I do place a live fish in the tank? At the moment, I seem to have more or less made myself a perpetual motion machine. Jeff