Little white tentacle thing attached to glass

[nmb7895]

And when I say little, I mean about the size of a ghost shrimp's eyeball.

It's just a little white body and about 5 or 6 tentacles attached to the top, and it seems to sway back and forth.

What is it, and should I remove it?

[Brhino]

sounds like a hydra. What do you have in the tank? They can prey upon small shrimp and fish fry.

[nmb7895]

sounds like a hydra. What do you have in the tank? They can prey upon small shrimp and fish fry.
I have nothing even remotely small enough in my aquarium.

The littlest things in my aquarium are baby ramshorn snails, but they're even larger than this thing.

Other than that, I only have a bunch of smallish (tetra sized) fish and similarly sized shrimp. And 3 giant snails.

[Brhino]

well, anyhow, do some googling on Hydra. That should help you confirm if that's what you're seeing, and help you decide what to do about it.