I've just finish setting up my marine tank. Now into week 6. And I have just spotted This inbetween the rocks. Can anyone tell me what it is please? Could anyone tell me if its friend or frool before I put fish in please.
Bristleworm. Creepy looking, yes, but beneficial scavenger. It will not harm any fish, inverts, or corals. DO NOT touch it! Those bristle spines will break off and hurt like a mutha.