clean up crew requirements

[dunl]

Well, a bag of shells from Michael's craft store outfitted one of my hermits with new digs on the first day (thought I had a dead hermit until I spied a nice, new, white shiny shell zipping along....), so hopefully there won't be any cannabilism going on there.

As for brittle stars, I forgot to mention that I have two of them. I'm liking the job that the turbos, hermits, and stars are doing so far, but I have a sahllow white sand bed, and I'd really like to get that stirred constantly if possible to keep it white instead of greenish, brownish, left-over-algae-colored.