Easy to use Each filter will treat a system up to 300 litres 3-watt air pump is sufficient to run each filter (not included) Media: 300ml of ZM-1 included Smallest moving media (ZM-1) Excellent Biofiltration by direct oxygen supply Stable filtration by self-cleaning filter media Physical filtration by contained filter sponge Made from High-quality material Made in Korea Size: 25cm x 7.5cm Filter Volume : 600ml