Hi,
I'm just getting back around aquariums again, and I'm slowly remembering all the how's come's, why's, when's. etc. But I'll try to help:scratch:
I think the brown stuff is more of a diatom type thing going on.
Gulp, you right at the point with your aquarium that the brown stuff likes to show up(from my experience). The best thing I know for you is to do the waiting game

Usually anywhere from a week to maybe 3 weeks. Then the green stuff will come around and you get to start playing the what can I do to lower the organics of the wonder system I have without compramising this that and the thing.
jeffro, how long has you tank been going?
P.S. I don't have much experience with cichlids except for my Frontosa. He tries to rip plastic plants apart, and pretty much acomplishes it too, he has a down right atred towards them! lol
But, if you can grow plants with buna's, is there any possibility that you could get away with Oto's in there(I am thinking this is a rediculas idea, but, never know). Oto's Love that brown stuff. Maybe 4 in a 55 would have it gone in a week(as bad as yours sounds). 12 of'em would be knocking on the glass the next day for algae waffer's
