Well I set my 58 gallon tank up almost 4 weeks ago it has a penguin emperor 400 filter after letting it run a couple days I added 2 sa cichlids water was good and clear, got a little cloudy the next day but cleared up in a day or two, I then added a rainbow shark and pleco a week later ( pleco and shark have been in the tank for 2 weeks) ever since adding them the tank has been really cloudy and the nitrite has been sitting steady at 3. I have been doing water changes, cut back onthe food and nothing is helping. it kinda seems like the filter isn't even working. As it sits right now nitrates 10, nitrite 3, gh 150, chlorine 0, kh 180, ph 7.8, ammonia 0. Can anyone tell me what's going on with this thing?