I've had my 55 gallon freshwater tank up and running since around last Christmas and I continue to have issues with water clarity. I've been using a conditioner called Acurel F - 25, which claims to suspend particles in the water which allow them to either settle or become filtered out. The product is organic and supposedly non-toxic to the fish. It does a remarkable job, but I can't help but wonder as to the cause of this problem in the first place. The tank came was a kit and has a large dual cartridge filter, not an under-gravel system. Admittedly, I've got perhaps more fish in there than I should, but seemingly within the 1" per gallon rule I've read about here. I was pondering getting a second filter, but I'd rather not go through the expense if ultimately it's not going to help. Given the novelty of our new set up, we do a good job maintaining the tank, so I'm doubting it's due to neglect. Any of you fish experts have an idea what's causing this continual problem? The tank just looks so much more attractive when you've got that crystal clear water!