Pawfly Filter Floss

Floss catches what sponge lets through: fine fragments, uneaten food and fish waste, held in a dense web of polyester fiber. There is nothing to measure or cut. Tear off a handful, spread it evenly across the filter chamber and let the water push through. The fiber is soft and fluffy, so flow keeps moving while the strands hold particles.

Bags run 7.0, 8.8, 14.1 and 17.6 ounces, so a reef sump and a small hang-on can each buy the amount they use. Rinse the floss and reuse it until it turns thin or worn, then pull a fresh piece. Floss does fine mechanical work and little else, so pair it with sponge or ceramic media for biological filtration in the same chamber.