Lees Undergravel Filter is the key to providing a strong biological filtration system. Undergravel filters utilize your tank's gravel substrate as a filtering surface area while providing oxygen to help aerate your aquarium water.
Placed on the bottom surface of the aquarium, the filter plates utilize the gravel bed as a source of surface area for bio-filtration and provide oxygen by recirculating the water down through the media and up through the uplift tubes.
The advanced design allows separate plate installation and features optional flow-thru setup, which can be used with a powerhead. Adjustable 1" uplift tubes provide superior water circulation. The filter is made of special, premium quality plastic which resists splitting and cracking.
Note: Must be attached to an air pump or powerhead (sold separately).