OK...I have ordered the equipment and everything is on the way. I can't wait to get started! Now, I knwo i still have some time until my tank is ready for some inhabitants, but I was wondering about something. On a number of sites (including here), I read about something called a "cleanup crew". From what I gather, they seem to be composed of crabs, snails, etc. For my 75G setup, with about 45 lbs of LR to begin with, what I should I look for in a "crew"? How much would be sufficient? What kinds? Should they come before I introdue the first fish to the system, or after? Thanks!!