[globaldesigns]

Personally I feel it wouldn't hurt, but after reading your post, I never heard of a clean up crew crashing a tank, unless maybe you had many of them die, polluting the tank.

I think clean up crews are worth it. I have lots of snails, a few crabs, and 7 sand sifting stars.

I had about 100 or so full grown snails, and now I must have hundreds of little babies that come out when the MH turn off, so they are breading. Which is good... I guess the only drawback is that I also get alot of little/empty snail shells, so they are dieing or being eaten. These shells clutter the sand, so once in awhile I use a fish net to scoop the sand and shift it to remove the larger particles and shells. Works well to clean things up.