How did the brown algae form in my tank?!

[JJHUNGZ]

My tank always get some brown stuff forming around the filter and on the glass of the tank, wonder if its algae or something, is there anyway to prevent it from appearing again?

 

[Countryboy]

I get the same thing. Since I don't have plants I don't mind it. I clean the glass with every water change and the filter intakes every other water change. I take out the rocks in my tank about every 2 months (if it starts to bother me) and scrub them. I think if you try cutting down on feeding and reducing lighting time it may help.