EHEIM reeflexUV reduces microorganisms in the water and eliminates turbidity more efficiently than ever before. reeflexUV is yet another typical innovation from EHEIM: due to a built-in reflector the microorganism killing UV-C radiation is significantly increased and whereas in conventional UV-sterilisers the water is directed via detours past the UV-C burner in the EHEIM reeflexUV water it takes the direct route. There is no loss of performance you need less energy and the level of effectiveness is 1.8 times greater.reeflexUV should only be used in conjunction with the filter in order to reduce small organisms (microorganisms algae spores etc.) in the aquarium. Benefits of the EHEIM reeflexUV:Quickly and efficiently reduces both harmful bacteria and fish parasites in their infectious stages in the water.Eliminates turbidity caused by algae or bacteria .Internally fitted high gloss aluminium reflects the UV-C light and ensures more efficient sterilisation.Excellent results with low energy consumption (1.8 times more effective than conventional UV-sterilisers) .No performance loss as using a special design the water is not redirected .Also ideal for breeding tanks as it reduces the risk of infection .Cleasing bacteria are safely retained in the filter as only floating organisms are captured.Simple safe maintenance and cleaning.AUTO-OFF: automatic safety cut-off when changing lamp.Easy to attach using the included fixing bracked..For aquariums 300l to 500l.