Oh, I never replied to your OP question. I've had both green and ruby emerald crabs with peppermints, kukenthalis, sexy shrimp, pom pom crabs, skunk cleaner shrimp, fire shrimp, Randall's pistol shrimp, and purple coral banded shrimp (haven't had normal CBSs or the golden/Zanzibar version)--no interactions between any of these. The emeralds sometimes have spats with each other, but so far only one suspected homicide (emerald on emerald aggression). I have not had them with arrow crabs before. Had a decorator crab once but evicted him within 2 hours after he boldly went to town on ALL of my coral, just.. all of them.. taste testing everything.. kept shooing him away with a pipette only for him to settle on another coral and munch munch munch...
