brown stuff on rocks?

i got this brown stuff growing on the rocks and know its getting on glass. anyone know what this is and how to get rid of it? my tank is about a month old.


Probably Diatoms. Very common for a new tank. Google image search it and see it that's what you've got going on.
Get rid of the damsels.


ah yea. diatoms. im going through the same thing. kinda makes me made that it covered most of my coraline algae when it started to grow but the LMB is havin fun eating it all as well as my snails.