sounds like a baterial bloom
LOL! No I've had this problem before but I'm having difficulty determining what the problem exactly IS...You've been a member here since july 03 and this is your first bacterial bloom ???!!!
If it's a new tank, you've probably got a bacterial bloom. Leave it be for another week, just do a 50 % wc in 7 days, and things should take care of themselves.
If your water has taken on a greenish tint, or it doesn't clear up in another week, you've probably got a GW outbreak. Then you'll have to do a blackout or use a UV sterilizer.
Give us some specs on your tank and we can better diagnose your problem.