Chris, red slime / cyanobacteria can be indicative of a problem in your tank, or on a limited basis, can be part of a tank's initial cycling. While there are quick fixes that will kill the cyanobacteria, the more prudent choice is to address the root cause and let the problem take care of itself.
The usual suspect is a 'dead spot' flow-wise in a tank. Cyano thrives in low flow areas, so often the addition of a powerhead, or upgrading your pump can make the problem go away. If you have bad green hair algae problems, the bed of all that algae can restrict flow and let cyano grow (quite a double-whammy that I've experienced only once, thank goodness.)
If you're overrun with cyano, a product called 'chemi-clean' will kill it, and is pretty safe for tank inhabitants, with one caveat. If you dose chemi-clean, you really MUST add additional aeration (either airstones or air venturi on your powerheads.)
HTH,
