I actually just dealt with a similar situation, do you have a bubbler? if not get one as soon as you can, the bubbles cause the surface to break allowing oxygen to get into the water, plants may not be enough.
as for the water change, how much did you take out? I would do a 50% water change including vacuuming the gravel. this will help remove ammonia which the levels may be high in your tank.
Also look closely at your fish, are there any white spots present? my cloudy water experience was agitated by white spot disease (ich). you should probably treat the water with either an ammonia binder if it is only bacteria becasue ammonia is lethal to the fish or a broad spectrum parasite treatment, if you see the white spots.
the bacteria bloom could be caused by over feeding, leaving a dead fish in there too long, the bacteria feed on the organic matter left over from these things. So by watching your ammonia levels and reducing your organic matter (feeding less perhaps)it should clear up over time
above all else increase the oxygen!
hope this helps somewhat... also see
http
/www.fishforums.net/index.php?/topic/246850-bacterial-blooms-explained/