What type of anemone is this?

[hillegom]

Looks like aiptasia. = bad
Does it have a hard tube to retract into? Touch it and see. The tube will not get shorter in that case

[saltwaterseahorses]

so touch it and see, and if it sucks in the tentacles, then its........? aiptasia

[04scoobysti]

How big is this anemone? I've never seen aptasia grow larger than 2"-2 1/2" across.
Although this does look similar to aptasia, I dont think it is. The tentacles seem too numerious and fine in your picture.

[saltwaterseahorses]

its pretty big