just noticed this, im assuming it is, i know there is another one the same, that is living inside a hole on a near piece of live rock - as well as one i have growin in a 5 gallon for the fun of it.
Im asking cuz i usually see Aiptasia as taller polyps, all these ones are flat against the rock with just tenticals out.
not to worried about them, either break them off and throw them in the 5g with the others or get a peppermint or two.
cheers