This is a fully submersible unit that controls water-born algae and prevents the spread of disease.

� Glowing monitor halo ring visible from any angle immediately shows that it's working

� Comes complete with 9000 hour, 20 watt lamp, the longest lamp life available

� Also includes water tight quartz sleeve

� Comes with transformer and 18' grounded power cord

� 1 year limited warranty

� 1 1/2" inlet and outlet with 3/4", 1" ,and 1 1/2" stepper barb

This 20 watt unit is for large ponds up to 3000 gallons using pumps up to 1800gph. It will clear green water in 3000 gallon ponds with a pump range of 900gph to 1800gph. It will kill many bacteria in 1000 gallon ponds with a pump range of 500gph to 700gph.

Great for aquarium use as well at the lower flow rates.