I set up my 2.5 here @ work on 2/7/05 (a tad over a month ago). The water is starting to get pretty cloudy (yellowish). I performed a 40% water change exactly a week ago (3/8/05). It looks like I'm getting some brown algae build up. Isn't an aquarium supposed to "bloom" about a month or so after being set up? What I understand "bloom" to be is a sudden bacteria and/or algae growth....ah! well, I JUST found this site:http://www.drhelm.com/aquarium/cloudy%20water.html & I think it just answered my question! I am using one of those UGF active carbon filter thingies! Guess I'll change it & hope it does the trick!