Review on Honritone 7 Inch Ring by 18 Inch Long Filter Sock Bags - 1 Micron, 5 Micron, 50 Micron, 100 Micron - Aquarium Felt Fabric Sump Filter Bag - 1 Pack by Daniel Teller

I've worked hard to learn how to use the sump filtration system. After a few years, a layer of brown sludge formed in my sump, which spilled into the tank whenever there was a disturbance. I got it wrong I added one of these and swirled the sump over me (bypassing the tank) and cleared out all the mud. I had to put on and clean the sock half a dozen times in one day. I've had the system fine for a day now and the water looks fantastic.