How Aquarium UV-C Sterilizers Work from A to Z

[Carlrs]

"AQUARIUM OR POND ULTRAVIOLET STERILIZATION

How UV-C Sterilizers Work from A to Z;"

Understanding the following points is ESSENTIAL prior to purchasing ANY UV Sterilizer regardless of brand or stated capacity (as most stated capacities are incorrect, even by the better units).
It is also noteworthy that many UV Sterilizers CANNOT achieve these points & in Fact are ONLY clarifiers and thus are a waste of money if one desires TRUE level 1 UV Sterilization (or higher)!!

• Flow rate
• Dwell time (related to flow rate)
• Water Turnover in pond or aquarium per hour
  *As well the circulation pattern can affect UV Sterilization effectiveness
• Distance of UV Lamp from UV Sterilizer containment 'wall'
• Temperature of water
• Pre-Filtration including Turbidity of water & a healthy bio filter.
If turbidity is high and bio filtration is low, you could require double rated UV. In ponds in particular, it often takes double the normal rated size UV Sterilizer if bio filtration is poor and turbidity if high just to clear green water.

Reference:

http://www.americanaquariumproducts.com/AquariumUVSterilization.html