what's growing on my hermits shell?

[wcfost]

Here's a photo. Is it something I should remove? This is my first SW tank, about a month in, and I've had the hermit for about 2 weeks.

 

[Jgomez324]

Coralline algae on his shell,Not sure what that thing on the top of the pic is. Aphasia?

 

[boxer]

coralline algae, its normal.

 

[wcfost]

Yeah I meant the thing on the top.

 

[3Twinklets]

It looks like some kind of anemone or aiptasia. If it was mine, I would take it off. It will only get bigger.

 

[Pkunk35]

Looks like a feather duster to me. They grow all over my tank and on my hermits. If it retracts quickly and is white, its a duster.