hi all
could anyone shed some light on the quality of "'pond medic'" uv lights. the reason for this question is that i have already had the supplier replace the unit as the tubes lasted a maximum of 5 weeks . i have replaced 5 tubes in 6 months. the first tube lasted around 2 weeks. since the unit was replaced in may 09 i have replaced 2 tubes , 1 being this evening. there is nothing wrong with my electricity supply as i have had it tested. the unit is fitted at the discharge side of a pressure filter.am i using the correct tube which was supplied by the supplier?(germ 15 t8 15w uv ce ) should i contact the supplier again or should i just replace the unit with another make? or is there someone who can shed more light on the subject.
regards

Did you install the UV with inlet and outlet facing upwards? By doing it what way the UV will be fully submersed in water.

Do you switch the power off to the UV when you do maintenance on the pump / filter? Do not run UV dry

I don’t know the size of your pond or the flow rate of your pump, but remember that it is important to have the correct flow rate in UV to obtain the correct contact time with water for UV to operate as it should.

I have not connected my UV on / off switch directly to the mains, but connected it on the power line going to the motor. By doing it this way, the UV can only be switched on/off while motor is running. Whenever you switch the motor off the UV will be off as well. I have also mounted the UV lower than the motor to ensure the presence of water in UV at all times.

thanks for the response Marius. i fitted the uv with the in & outlet facing the pond as the the instruction on top of the ballast housing . uv is +_ 300mm lower than the discharge line of the filter .15 watt uv with flow rate at 3000 l/hr. maintenance is carried out with uv switched of and only turned on once i have the pump primed and fully operational.gathering that you have not commented on the make , i take it that there is nothing wrong with the make.
hope you have more info for me
thanks

Does the tube glass break, or is it just stop working?

Hi Marius
the tube does not break , it just fuses , like blown . the glass turns a chrome kind of black

It might be a bad contact somewhere. Have a look at the connections on either side of the tube.

http://www.repairfaq.org/REPAIR/F_appfaqg.html#APPFAQG_002

http://www.naturalhandyman.com/iip/infelectrical/inffluor.html

done checks on all the electrical connections . i'm lost . please suggest an alternative make / brand , maybe the brand that you are using
thanks

Many people are using the Ultrazap UV

http://www.ultrazap.co.za/html/uv.htm

thanks Marius
any comment to my last post ? (biofilters)

How true is the following statement that can be found on various internet sites????

‘’Kills good nitrifying bacteria that pass by the UV so it must be shut off during spring to allow bacteria to get started and whenever there is a die off of good bacteria.’’

I am running 3 x 55W UV’s on a 30000L pond and they are installed BEFORE the filter chambers, since I pump-water-to filters.

Was just wondering how other people feel about UV’s running 24/7. I have switched mine off about 2 weeks ago and forgot to switch it back on. Water still crystal clear which might be a sign of the pond maturing

Hi,

I came to the conclusion that UV-lights are a waste of good money!
Yes, I did fit UV-lights to my pond systems, but I switched it off after about three months of use as it made no difference to the quality of my pond water.
If your filter system is adequate to handle the water and Koki volume in your pond, no UV-light is necessary even if the pond sits in full sunshine.

When my pond was still new about 3 months old i found it going a little milky then found that my uv was off i turned it back on and after a few days my pond was crystal clear and have had it on ever scince 24/7 but will turn it off when i get home early nov to see what happens. i only have about 7 hours of sun on my pond each day then it is only 50% of the pondat this time of the year, in winter i have no sun. is sun good or bad for the koi in middle summer they have very little shade is that a problem???

Hi Angry

You can check this link out:

http://www.nishikigoi-info.com/koi-care/sunlight.html