I've been using the Unicel cartridges for about 1 week now, and cleaning them out every evening. You wouldn't believe the difference it has made! Nearly all of the gunk has been filtered out and the water is clear. I just have to stir it up once or twice a day because the gunk that's left keeps settling to the bottom. It's almost completely out of the water though. I would highly recommend the Unicel cartridges to others with similar problems.