unidentified smears on glass

[pinstripe]

My [second-hand, still dry] tank has patches of residue on the inside walls. It's clear/cloudy, and I've never seen clear algae. Water beads on it as if on a greasy smear, but it is slightly rough to the touch. Soap, vinegar and scrubbing have no effect.

Any idea what it is or, better, how to get rid of it?

 

[mr86mister]

probably a stupid question but

is your tank full of water or is it an empty tank?

*if empty* could be any type of oils or residue if something spilled

*if full* maybe some kind of bacteria or something from a creature you have in the tank

how long has it been there?

(sorry to grill w/ questions...lol)

 

[pinstripe]

Nope, tank is empty. Residue was there when I got the tank from its previous owner. It *looks* a little like algae or mineral deposits, except (1) clear and (2) doesn't come off in the "usual" ways I know about.

 

[Blazeherd2306]

Have you tried scraping it off?

 

[pinstripe]

Took an exacto knife to it just now -- it made a dent in a few places, but mostly there was no effect.
Is it possible there's fog inside the glass?

 

[QTOFFER]

It might be silicone from a sloppy reseal job. Did you try scraping it off with a razor blade?

The only other thing I can think of is that the glass may have been etched by a harsh cleaning chemical.

 

[mr86mister]

hmmm...what size tank is it...because i beleive it just would be one piece of glass, maybe if you can get a picture of it for us it could help

 

[DirgeDevil]

I'd try putting the tank in your tub (if it fits) and filling up the inside with warm water with some aquarium salt and letting it soak overnight. it might work, it might not. but it helps me clean normal algae off of my fake plants and decor...

 

[pinstripe]

Thanks, that's helpful!