I put the fabric in net bags when washing. I have very little fraying and no knotting up as long as I fill the bag with enough fabric that it can't roll around in it. I can put several pieces of fabric in one bag and can put several bags in the wash at the same time. I got my bags at Walmart near the laundry baskets. The bags come in a couple of sizes. You just have to watch and put like colored fabrics together. Even using Color Catchers, I had red dye spread to another fabric in the same bag that had a light design on it. Only other problem... I haven't found a big enough bag to put more than three yards in.