Strange creatures on my glass in sump, no pics

[raynist]

I have a bunch of these little creature growing on my sump glass. They are maybe 0.5 inches and are a little thicker than a piece of hair. As the water passes over them, they elongate to about 1.5 inches and then retract. Anyone have any idea what this may be?

 

[Travis L. Stevens]

I'm going to venture a guess here. Is it a Coeloplana? They are jelly like creatures often called "Comb Jellies" These Ctenophores attach to the glass and spread out their tentacles and when something touches it, it retracts them into their mouth. Very awesome critters to watch. Oh, and they are mobile.

Is this it? (more of an overhead view)