Brown Fragile Algae

[wwest]

ok, my friends 120gal tank was infected with red algae, we treated is as directed and the red algae went away. however after it went away the "plesent" yellow shade was in the tank. we cleaned it and then a few days later we started getting alot of this medium brown looking algae all over the tank. we cleaned it and within two days its all over the tank again. does anyone have any ideas? this stuff is a pain in the rear.. its in the sump and the display.. also it is very easy to clean..

thanks in advance..