I've kept a 90 gallon reef for a few years. In saltwater, you aren't really going to find cleaner fish, you will need a cleanup crew composed of snails and maybe hermit crabs. You will want some sort of mechanical filter-a small power filter would work, and you may want to look into a nano skimmer. For supplies, you will need sand, rock, a relatively powerful light if you want to keep corals, and of course, salt. I highly recommend joining 3reef. It's a great forum for all things saltwater.