Don't really know where to start on this one... not like any flat worm's I've seen...

[USFnano]

I just noticed this little guy scooting around my fuge. It's about 1.5" long, maybe 1/2" wide, but only paper thin.

 

[Acoustic]

There are large number of flatworms that are found in reef aquaria. Most of these are harmless or, at worst, nuisances that do not directly harm most of the animals in the aquaria. However, in nature, coral-eating flatworms abound and occasionally they find their way into our systems, probably entering on wild collected or captively grown corals.

 

It looks like a coral eating flat worm. Here's a picture of one:

[enrico]

Sorry but it seems a flatworm as "any other". Flatworms that eat corals usually come with the coral colony they eat... By the way keep an eye on him!

[ricky1414]

i tried to get a rather large one out of my 50 gal after it started to munch on my corals. he was huge, like 3.5 inches long. to make a long story short, he disintegrated into like wet tissue paper, i got out most of the body, but the toxins released killed off several of my fish:( turned my water real cloudy. 5 or so water changes later, all was good.