It's not dying and it wont happen that fast. if it's floating around in the tank, some air pockets with it (Airbubbles coated with brown substance) it's actually muliplying. the lage mexican tubo snails will eat it but beware they knock over rocks.
the absence of light will not remedy the problem.
even with a ro/di filter you will still have Phospate in your tank due to the high bio load.
you need to run phospaban or reduce the number of fish in the tank.
moving to a larger tank right now wont help even though you are going to swap everything over your tank will be out of "whack" and the algae will flourish
Tony I have the Prizm too and it works great on a little tank. And the tap water filter too I like it but am going to invest the 100 bux for a real RO/DI unit.
My tank is only 29 gal too.
thanks nypd i figured that. its actually not floating around in the tank. its on top of the water. i put in that phosphate stuff. so hopefully one of my problems is gone. now i gotta get me the rodi and cure this algae problems so i can move everything over to the 75 gallon. patience is key. thanks everyone for the helpful advice. chief the best thing to buy is that rodi. after x-mas ill buy one.