Pisces Replacement 11 Watt UV Bulb for Laguna Pressure Flo Filter PF5000 When regular maintenance is undertaken on any pond filter or UV the results are clear within the pond. UVCs ensure pond algae clumps together to enable the filter to remove it effectively from the pond water Ensuring the UV lamp inside any filter or UVC clarifier is replaced regularly gives additional benefit to the pond and life inside it. These linear UV bulbs are unique and different to the majority of UV bulbs on the market. Each bulb has 4 pins located at just one end. Each end of the linear tube has a ceramic tip. The tubes are designed with a slimline clear glass centre to maximise their efficiency. 11Watt will fit the Laguna Pressure Flo PF5000 (will also for the PF2500) Dimensions : 225mm