NEW high wattage compact UV lamp system which enables twice as much light output as linear lamps. Effective long-term control of green water. 18w UVC suitable for ponds up to 16,200 litres (3,564 gal). Twice the UV output - Advanced power compact UV lamp system enables twice the UV light output in the same installation area compared to conventional linear lamps. Low running costs - Low pump back pressure contact chamber combined with efficient power compact UV lamp. All fittings supplied - Multi hosetails to fit all standard hoses and solvent weld 1 1/2\" pipe work adapters included. Flexible modular design - Any number of Blagdon professional UVC units can be connected together via optional wide bore link pipes. Unique linking system enables simple future expansion to meet your needs. NOTE: UVC bulb included.