UVC, lamp, quartz sleeve, bulbs and water clarifiers, find out how it all comes together in your pond

Mechanics

The water is pumped from the pond into the sterilizer unit where it passes over and around a glowing ultraviolet tube protected in a quartz sleeve. The effect of this is to damage the unicellular green algae to the extent that they die or clump together and are filtered out in the biological filter where they are digested by the colonies of aerobic bacteria. Some manufacturers claim that it makes them 'stick together' and this makes them easier to trap in the filter medium.

"MUST DO's" IN ORDER FOR U/V LAMPS TO BE EFFECTIVE

They must be used in conjunction with (before) a filter or the dead algae just returns to the pond to rot on the bottom and become detritus for less benign bacteria to feed on, or at best, to provide nutrition for the next generation of algae.

They do not sterilise the water. They do very little to help produce pure water, but they do help us see what is going on in the pond. That is if the water is not cloudy merely because of mud being stirred up by the fish.

PROBLEMS : NOT WORKING EFFECTIVELY

1) It is essential that the specifications of lamp i.e. the wattage, matches the requirements of the biological filter and the pump providing water for the system and in turn matching the gallonage of the pond. Example: 8 watt lamp, 250 gallon per hour pump to the height of the filter, turning over the complete volume of a 500 gallon pond every 2hours. 15watt lamp, 500 gallon per hour pump and a 1000 gallon pond.

2) Is the bulb still working at all? Never look at the working bulb itself. Try to see if there is a glow through the fittings at the ends or up through the hose tails. Do not dismantle it unless it is not working. The fact that these units have to cope with permanently damp conditions, it is inevitable that the dampness finds its way to the electrical connects of the plugs and the bulb fittings. The connections are usually unstable alloys that build up deposits inhibiting the electrical contacts. These deposits very often 'weld' the connections together and often make it virtually impossible to service the unit by taking it apart without breaking the bulb. So as the saying goes let sleeping dogs lie and only take it apart when service time is really here. Then when you do get it apart, put it back together with a very thin smear of waterproof grease or Vaseline on the connecting parts.

Designs have improved over the years and this is rapidly becoming a problem of the past.

3) The lamp/tube needs to be changed every 6mths (yearly with some units nowadays). Even if it is still working its effectiveness is diminished in this time.

4) Beware of calcium deposits on the quartz sleeve or the tube within which the bulb is contained. They reduce its effectiveness. Manufacturers often recommend regularly changing them too. This generally occurs any way since as the unit gets older, they are very often a casualty of bulb the bulb extraction performance.

The lime deposits can be prevented by another add-on in the form of a specially designed magnet on the inlet end of the water supply to the u/v Clarifier.

MAGNETIC TREATMENT or 'IONIC WATER PROTECTION'

The precipitation of lime scale on the inside of pipe-work and u/v silica quartz sleeves affects the performance of both pumps and filters. It is claimed that magnetic treatment of the water acts on the calcite minerals affecting their ability to form scale. Therefore used in conjunction with a UVC (see above) the performance is enhanced.

Of secondary benefit is the reduction of blanket weed. The ability to absorb these minerals seems to be essential to its growth. Once the magnet affects these minerals it is unable to do this, which manufacturers claim, results in its 'virtual elimination'.