What's going on with this Acan?

[nicholas.babb@gmail]

Hey,

Added this acan frag in about two months ago and, since then, it has been doing really well and is sprouting several new heads. However, when I woke up this morning it seems like two of the existing heads are either splitting apart or have substantial tissue damage. The heads are not retracted, colorful, and show no other signs of stress.

Water:
Temp: 77-79
Salinity: 1.025
Nitrate: Undetectable
P04: Undetectable
Alk: 8.6
Calcium: 420

Picture posted below. Thanks in advance.

 

[Willz]

Do you have any peppermint shrimp in the tank?

I had some that were definitely tearing up my acans once they ran out of aptasia.

 

[nicholas.babb@gmail]

Do you have any peppermint shrimp in the tank?

I had some that were definitely tearing up my acans once they ran out of aptasia.

Just a fire shrimp who I have never seen bother any of the acans. Two Halloween hermit crabs but I don't suspect them as culprits.

 

[ahiggins]

Do you have any peppermint shrimp in the tank?

I had some that were definitely tearing up my acans once they ran out of aptasia.

I agree!
I had a pep shrimp run out of aiptasia and he did the same thing to one of my rainbows-seems like he liked the bright colors >.>
It grew back together but still has a little dip where the tear was. Ive also seen, as your pic shows you, one head split into two heads. Ive never found any documents supporting that type of thing but Ive seen it on one of my red acans.