The Amalgam Submersible UV 40 watt are the most effective form of uvc to date !
The Air Aqua Amalgam provides radiation with a wavelength of 253.7nm which is generated by the special light source UV lamp, Ensuring a lethal effect on bacterial.
The  Amalgam UV radiation neutralizes bacteria, viruses and other primitive organisms, stopping them form multiplying. The unit has a built in high frequency electronic ballast which absorbs current fluctuations and protects the lamp inside the unit.
 
Specification:
Amalgam Submersible UV 40 watt
For Ponds up to 35 m3 – 7500 gallons
Energy-saving: Amalgam saves 50-70% compared to normal TL-lamps
Optimal operation up to 16,000 (amalgam) hours
Short length: ideal for integration for Sieves or Drum Filters
No resistance in the system (from extra pipework)
Length 50 cm
 
The Amalgam Submersible UV 40 watt lamp is not affected by temperature fluctuation in the water and generates a constant powerful output and is know as being the most powerful uv-c on the market !