The use of type C ultraviolet radiation (UV-C) is the most effective way to sterilise water. No chemicals are involved and there is no risk of dangerous overdosing. Long process times are not required as sterilisation is instantaneous.
The highly concentrated UV-C. energy exerts a lethal effect on living organisms. It alters the genetic material (DNA) and inhibits their reproduction capability. The germicidal properties of UV-C radiation are therefore extremely beneficial in destroying bacteria, viruses, protozoa, algae, yeasts and mould spores. Different types or pathogens or bacteria require different levels of radiation to either kill or to stop them from functioning and multiplying.
D-D U.V. Sterilisers are designed to produce a radiation intensity of 30,000 microwatt's/sec/sq.cm which is sufficient to destroy most common pathogens in fresh and salt water aquariums however if required the intensity can be increased by decreasing the flow rate through the unit.