ID please?

[mkorolev]

This thing is so weird...and kind of cool...in a slightly creepy way

It seems to behave like a snail. occasionally "surfs" the currents to get back down, and it seems to be shedding some of the "tentacles"

There was a nem in there, which i can't find now...so i'm wondering maybe it uhh..."mutated" into something?

here are a couple of videos:
View My Video 1
View My Video 2

there's a "bump" on its back that's visible in the second video that look slike it's breathing....

 

[SushiGirl]

Some kind of nudibranch. What does it hang out on? Whatever it hangs out on (or looks like) is usually what it eats.

 

[mkorolev]

Some kind of nudibranch. What does it hang out on? Whatever it hangs out on (or looks like) is usually what it eats.

Thanks.
The glass the and powerhead, mostly..he's all over the tank. I'll keep an eye on him.

 

[MichaelDavid]

It kind of looks like a berghia nudibranch. Although, I'm not 100% positive. If it is a berghia, that's a pretty cool hitchhiker as they eat pest aptasia anemones.
Hth