Fits Aqueon QuietFlow Filter: LED PRO Size 20 & up and E Internal 40 gallon
The ready-to-use cartridge contains high quality activated carbon that keeps water clean, rinse before replacing
Installs in seconds: align cartridge bottom key slot for an accurate fit inside the Filter
For optimal performance, change approximately every 4 to 6 weeks
Do not clean Bioholster when replacing the cartridge as it contains beneficial biological bacteria