What is my cleaner wrass doing?

Question

It's in a hole in a the rock and it looks like there's a cacoon or web like thing around it?

Answer 1

That's (sort of) normal for a wrasse. It's how they protect themselves when they sleep, although some burrow into the substrate before they enclose themselves in their mucus layer. Yours may just be telling you it doesn't like your substrate (maybe the particles are too large or too sharp to burrow comfortably). Use this chart to see if the type you have is "burrower friendly": http://www.caribsea.com/pages/products/dry_aragonite.html

Answer 2

WHAT!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
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