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 33,000 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.
Transmission loss: Many people are aware that quartz is 96-98% transparent to UV-C and that normal glass reduces its transmission by approximately 50%. This is why U.V. Sterilisers have a quartz sleeve between the water and the bulb.
What many people are not aware of is that conventional UV sterilisers produce the UV radiation from a conventional glass tube therefore half of the intensity is lost before it even leaves the tube.
The D-D Professional UV Sterilisers feature a pure quartz bulb as well as a quartz sleeve so 98% of the UV-C produced is utilised.
In effect the D-D Professional models produce approximately twice as much UV-C per watt than a conventional unit with a glass bulb.
This makes the units much more compact and easier to fit into many aquarium cabinets. The remote electronic ballast is very compact. Features and Benefits. Slim line high intensity quartz bulb with ceramic cap for good thermal insulation. Lamp life of 9000 hours for continuous use. Electronic Ballast for flicker free operation, doubling the bulb life. Pure Quartz sleeve prevents thermal shocks and maintains the lamp at the correct temperature (40-45 C) for maximum UV-C output regardless of the water temperature. Reinforced UV resistant plastic body prevents degradation with time. Single ended design and waterproof insulation to CE IP67. Allows the unit to be partially submerged in a sump thus reducing the space required for installation. Viton gasket for a long term UV resistant seal. Specifications Model Number - RUW202 Replacement Bulb - RUW252 Replacement Sleeve - RUW255 Wattage - 20 watts Flow Rate - 1000 lts/hr Dimensions -600mm x 100mm x 140mm Suitability Reef System - (1-2 times turnover per hour) - 500 to 1000 litres. Fish System - (2-4 times turnover per hour) - 250 to 500 litres.