ID This glass stuff?

[wrek]

It's slippery but comes off the glass very easily. I can feel it when I rub my hand on it.

 

[wrek]

They're really hard to focus on.

 

[BettaFishMommy]

from what i can tell in the photos, you may be experiencing an excess of beneficial bacteria building up on the glass, or it could be the beginnings of hydra. either way, step up your water changes and tank maintenance (both in amount and frequency) and you should see that 'stuff' go away.

 

[NYCguppydude]

Biofilm.

 

[heislertj]

It is a natural occurence of bio film. You should wipe down the inside of your glass during water changes. I like to leave it on the back glass because it doesnt affect my view and if I am lucky, I will get algae growth so my plecos will be happy....it could get out of control if you have a newly set up tank or not enough water movement in the tank...either way...more frequent water changes will definitely help.