Ultraviolet Steriliser / Clarifier
Microorganisms such as disease pathogens and single-celled algae (green water) can be destroyed by exposing the organisms to ultra-violet light. For the process to work, water carrying the organisms must be exposed to the correct intensity of UV light for a suitable duration. In order to achieve this, ultraviolet sterilisers and clarifiers pass water through a sealed unit in close proximity to an ultraviolet bulb.
Sterilisers and clarifiers differ in the level of UV light exposure to give preference to killing either algae or disease pathogens. Clarifiers are usually used to remove algae cells in ponds and allow a higher flow rate to suit pond filtration systems. Sterilisers are used more in aquariums and will kill disease causing pathogens (such as bacteria and small parasites), but require a slower flow rate.