I started to feed my guys when I noticed on the other side of the tank a yellow looking slug. It's body looked like a slug and it's head has two large bulbs. Does anyone know what it is and is it harmful to coral? Here's a pic. Sorry about the quality.
Looks like it could be an Anaspidean slug, and likely a harmless herbivore. Does it seem to graze? How big/small is that sucker?
In any case I doubt if it feeds on coral, as it has none of the stereotype features of nasties like Dendronotid or Aeloid nudibranchs (cerrata and such...).
If you want, you can try to pester Bill Rudman or any of the other fine folk at www.theseaslugforum.com for more educated guesses