well i went over to my friends house tonite and i looked into in his tank and i said holy s**t is that water cloudy. the inside of the glass was also very slimey. all of his water test come up fine. this cloudy water has been going on since a week after christmas or so. he got a lage castle and a medium size ship from petco for christmas and he washed it a could times before he put it into the water. after he put those into the water it started to get cloudy. so i looked at his power filter and it was over flowing so i had him put new filters in it and it still over flows. so i told him to take the black sponge what was in the filter and it did not do anything. so i had him take both medias and both black sponges out of the filter and it still over flows. his tank size is a 55 gallon and he got it from walmart and it also has a aqua tech 55 gallon filter for it. i think he needs to get a better power filter. please let me know what u think