Regina, I can't have much of a clean up crew for obvious reasons (2 triggers, and 2 wrasses). That said I find CC to be good in my tanks because it is large enough that you can vaccuum it without sucking much of it up....The negative is that it can build up nitrates, but this won't happen if you vaccuum it, I have yet to see any trates in my current tank. Also, I find my "aggressive" fish like digging around in it looking for food. Plus as Prime said, it is benefiscial to PH, I would disagree and say it helps long term as well.