Who's killing my chromis

[elvictre]

My chromis keep getting beat up, I meen they have chunks missing and there fins are all nipped up. I had 3 die on me allready and I replaced them only to have another one go. I was told that it could be my serpent sea stars, but I read that they are not aggressive. I have wittnessed my blue tang take an aggressive nip at one of them. I hate to let the others play out there time until they are tang bait. I have the following fish, 2 maroon clowns (about 1 inch), 1 blue tang (about 2 1/2 inches), 1 yellow tang, 2 dwarf angels, 1 sand sifting blennie, 2 serpent sea stars (that I have never seen out during the day), 2 sand sifting sea stars, 1 red linkia star. Would any of these guys attack my chromis? The only one that I read is semi aggressive is the clowns, but they are really small.
Thanks
Vic

 

[microman2k]

are the 2 maroons a pair? if so mabey the chromis are getting alittle too close for comfort to them, and in turn the maroons are getting aggressive to protect their territory. :notsure:

 

[elvictre]

Yes they are a pair. Are they that aggressive at such a small size? They are the same size as the chromis.
Thanks
Vic

 

[robchuck]

It could also be the chromis killing each other. Their social structure is very interesting, but they need to be in odd-numbered groups of at least three; and even then, they could still kill each other off. I played by the rule and had a group of five green chromis at one point, but after a few months, it eventually became a group of one.