Common Aquarium Filter Media and How to Clean Them

1 Aquarium Filter Media

1. Filter Floss

A fibrous pad for catching larger organic particles, placed on top of the filter, usually 3–4 layers. Clean only the top 1–2 layers. It hosts nitrifying bacteria, so rinse with clean water during water changes; clean about every 10 days and replace the innermost layer, putting new floss under the old.

2. Bio-Sponge

Traps large particles and grows nitrifying bacteria; placed under the floss. Its pores clog easily, so clean it regularly.

3. Bio-Balls

Widely used biological media that grow nitrifiers and improve water. Don’t keep them fully submerged or the bacteria get too little oxygen; place them where water and air mix so they work best.

4. Ceramic / Glass Rings

Great homes for anaerobic bacteria with strong bio-filtration, placed under bio-balls or used alone. More surface area means more beneficial bacteria; glass rings have 6–8× the surface of ceramic and breathe better, so they work better. Don’t clean often—only when coated with dead bacteria.

5. Activated Carbon

A chemical media under the floss/sponge. It adsorbs impurities, bacteria, and fine particles, but once its pores clog it stops working and can become a bacteria breeding ground, so replace it—about monthly.

6. Coral Sand

Comes in coarse and fine grains; raises hardness and grows nitrifiers; used in harder-water tanks and not usually washed.

7. Ammonia Stone

A porous media that removes ammonia ions and adsorbs toxic organics and gases, protecting fish—but it is ineffective in saltwater or high-salinity tanks.

9. Live Plants

Excellent biological filters that absorb most inorganic salts and harmful substances while beautifying the tank.

Many owners forget to clean and replace filter media—do it on a schedule.