SUNSUN JX-01 mini fish tank built-in filter pneumatic biochemical filter for aquarium replacement piece for filter media. These filter work in the same manner as sponge filters and provide excellent biological filters for small to medium size tanks up to 20 gallons or you can add multiple to increase tank size.
Built-in filter/filter sponge
Product description:
1. Use an Air line hose to link the filter to the air pump, then place the filter at the bottom of the aquarium
2. Turn on the power of the air pump and observe if the air bubble is normal to confirm the normal operation of the filter.
 
Get an Upgrade from a regular Sponge Filter!!