The hozelock ecopower previously ecomax has been a popular filter for over 20 years. Br this long heritage shows that it has it has always provided good qualities. Br now the engineers at hozelock have taken this box filter to the next level with an increased uv level and enhanced biomedia. The uv power is increased to 12 watts previously 8 and the static flocor biomedia has been replaced with k3 biological filtration media. Br this media has a neutral weight so actively floats around the filter bed creating a more dynamic environment in which healthy strains of bacteria can thrive. Br suitable for koi ponds up to 3,000 litres or goldfish ponds up to 6,000 litres. Br br note uvc bulb included.