My acan frag is doing well, recently I noticed that 1 zoa polyp grows on its base (in the pic is on the left side). Should I concern with this zoa and try to remove?
Hard to tell from the picture, but just make sure that isn't a majano anemone. They can look a little bit like zoa polyps.
Assuming it is a zoanthid, it is likely the acan is going to outcompete it and it will die. If it is in a spot you can remove, just frag it off and glue it to a piece of LR rubble.