MOAN LY 401 Mini Hang On Filter for Aquarium Fish Tank | 2.5W | 250 L/H Sponge Aquarium Filter  (Mechanical Filtration for Salt Water and Fresh Water)

LY 401 utilizes a fine sponge or filter pad to trap debris, uneaten food, and other particulate matter from the water. It incorporates a bio-media compartment where beneficial bacteria can thrive. These bacteria help in breaking down harmful ammonia and nitrites into less toxic nitrates, promoting a stable nitrogen cycle essential for fish health.