What is on my acan help!!!

[jennyQwQ]

It has tentacles on the brown tube thing, is this pest. I do feel like my acan is not very healthy. It some time have brown things going out from there.

 

[AllSignsPointToFish]

I can't tell exactly from that picture. Vermetid snails?

And welcome to R2R!

 

[steallife904]

hard to tell but if tubes probably vermetid snails. I would pull out frag and crunch them up with pliers or fill the holes with glue or putty. As I find them from time to time in my tank I just stick some putty in the tube when I am attaching new frags.

 

[KSUChemist]

I have similar vermetid on a hammer frag. Doesn't seem to bother the frag so I leave them alone.

 

[steallife904]

it will over time, I would get rid of it.