WHAT IS THIS??!? I found two!!

I haven't been on the forums much at all the last few months, but have still been active w/ my tank. Last night we made the transition from our 75 gallon acrylic w/ a marginally acceptable system to our SWEET new 90 gallon Oceanic w/ the starphire glass and all new setup. (clap)
When we were transferring the sump, I found this on my little charcoal bag. Then we found another on a rock. I have not had any issues in my tank lately at all. I didn't put them back in or try to keep it, I figured it could get out of even the tiniest holes in a container. I really want to know what the heck it is!! It's about 3-4 inches long, maybe 3/4 to 1 inch wide.



Just for fun, here is a before and after pics of my tanks. (rock2)

 

The tank and stand look very nice.

The ID in question appears to be a kind of flat worm (I think). Did you find it just recently?

 

Polyclad Flatworm.

 

Thank you!!

Yep, just found it last night.

 

Polyclad - good or bad? I'm googling now but if you have personal experience I would appreciate it!

 

Where there is one or tow) there is often more.

 

I pulled one out of my tank that looked identical to those. It came in Florida LR. I think it was responsible for eating snails. I would find empty shells in the morning.

 

Beautiful upgrade, and flatworms, can't remember if good, bad or indifferent. I would probably get rid of them.

 

If I recall correctly, flatworms are a bad thing to have.

 

Do you have any sps in your tank? -I see a birdsnest towards the top right.

These appear to be "acropora-eating flatworms."

Melevsreef.com - AEFW | Acropora Eating Flatworms