I'm having the exact same problem, it's a rust colored algae. My tank has been set up for about 2 months. The algae in my tank is also taking over all the rocks, which were originally white, and making it's way up the glass.
The process is more rapid in my 10g, though, and I've already had 2 ottos pass.
So I don't wanna get any more ottos... hopefully it'll go away.
The process is more rapid in my 10g, though, and I've already had 2 ottos pass.

So I don't wanna get any more ottos... hopefully it'll go away.