Brown algae

[arj]

My tank has been set up for nearly 4 months now, but for the past couple of weeks there has been a lot of brown algae appearing around the bottom of the glass and now going up the glass.

Whats going on?

 

[The-Wolf]

it is diatoms, nothing to worry about.
try increasing the light, either add more
or keep the current ones on longer.

ottos will eat it as will apple snails, other than that, it's time to get scrubbing.