Guys one of my anthias back and lower fins are turning black and purple. Very beautiful but is turning aggressive against other anthias (is not killing them just going after small anthias) is he turning to a male or what?
I believe I have the same thing going on. Mine tends to dart around the tank and does a head shake when others get too close. No nipping or anything though. It has also grown a large spike on the front of the dorsal fin.
The action reminds me of when I had my cichlid tanks. A lot of posturing going on.