Have a 55 gallon tank, had a yellow tang, 2 misbar clowns, a orangetail blue damsel, a pom pom crab, a chocolate chip sea star, a condylactis anemone and 5 hermits(for cleaning purposes) I have been battling cloudy water for weeks now. Everything was going fine for a couple of months, and then I added the anemone and hermits, three days later did my 5 gallon water change for the week, and I noticed before the water change it looked like the fish were breathing hard. The next morning I awoke to find everything dead but the hermits. Salinity @ 1.024, pH at 7.8, ammonia 0, nitrite 0, nitrate 0 phosphate 0. no cleaning or air freshners are used within 10 feet of tank. Temp stays at 80. I had a problem with my nitrates and nitrates going up, I upgraded to the marineland emperor 400 90 gallon filtration system and they went to 0 within 24 hours. My fish died a week ago. I tried to introduce a pseudochromis 3 days ago, but he was breathing hard during drip acclimation and died within 5 minutes of being put in the tank. What could be wrong? I'm sorry for the long info, just trying to be thorough. Thanks in advance.