TMC Pond Clear Ultraviolet Pond Clarifier UV8 Advantage is an 8 watt unit for green water algae control. The unit is positioned out of the water (i.e. it is not submersible) and requires a through put of water equal to at least half the pond volume per hour up to a maximum of 2700 litres per hour (600 UK gallons per hour). The clarifier is suitable for ponds up to 5400 lites (1200 UK gallons) in volume. Best used in conjunction with a pond filter to collect the dead algae cells and to break down the resulting ammonia (from the decaying algae). Supplied with a pair of multi step hose adaptors for lexible hose and a pair of 1.5" rigid pipe terminals. The unit has a 5 metre mains cable and is guaranteed for 36 months.