The advanced White edition APS 300 air pump is for use with all aquariums from around 120 to 300 litres in volume. With the external inline flow control valve included, the Tetra APS 300 can easily be adjusted to provide the right airflow for many applications. APS 300 specs Air output 300 litres per hour, two outlets (150 lph each), not adjustable. Wattage 4.5w Suggested for aquariums up to 300 litres, will operate two 15cm airstones in water 40cm deep. Guarantee 3 years, excluding diaphragm