My tank has cloudy water! last weekend, i replaced some of the bio balls in my filter. then within 2-3 days, the water had become very cloudy. the bio balls had been there for almost 18 mths, so i replaced almost half of it with new ones thinking it would provide larger area for bacteria and be more efficient in filtering ammonia.. I also ditched some of the bio balls, and the bio balls in my filter are now actually slightly less than previously. few weeks back my aquarium was in a very bad shape (now bad, but not that bad), and it had very cloudy water despite several large water changes. but after i've vacuum and cleaned the filter, it was ok until last weekend's bio ball replacement. i couldnt think of a better explanation. i've also increased CO2 and dosing about 10 days back since i've been underdosing all these while. previously, i've been feeding the fish once every 2 days, recently once a day. my filter's filtering rate (published) is 380l per hour. tank capacity 27litres. Any advise? should i just wait for a couple more days and see if condition improve?