Can anyone identify?

[Lambert58]

I know they are a flatworm, I have heard different people say that only the red flatworms cause problems. I have three different wrasses and a mandarin that ignore them, so my next option is flatworm exit if I need to get rid of them. As you can see the mushrooms aren't affected by them, other corals are doing well also. I first noticed them six months ago but since they were white/clear I ignored them on the above mentioned advice. There have multiplied, but they don't seem to be causing anybody harm.

 

[triggreef]

are they actually on any other corals?

 

[Lambert58]

Several on frogspawn, hammer coral and a few on the stalks of silver Xenia, but they definately prefer the mushrooms. Don't seem to go near zoas or palys.