How do you know if it's time to replace a UV lamp?

[Delphinus]

I swear the eerie little glow that comes out of my AquaUV is dimmer all of a sudden (I had to unplug it a couple days ago to get at a fish who had sumped himself). It's a unit with a wiper so the quartz sleeve is clean, so that's not it.

It's not like you can take the lamp out and check out the brightness that way, since UV is bad and all, so I guess my question is, how do you know if it's time to replace a UV lamp? Do they get dim? Or is that a figment of my paranoid imagination? Can I hook up the unit to a watt meter and if the watts used are less than the rating maybe that could confirm it's dim?

Or do they just burn out and that's when you replace them?

I have about 10 months of use on the unit.

[Mrfish55]

I change mine at 6-8 months if run 24hrs/day, at 10 months it will not be very effective, I believe they are most effective for only 4-5000 hrs.

[sphelps]

Diddo, it's just a time thing like any other bulb you use on your tank. About 6 months if on a full duty cycle, could potentially last a year if on half cycle.

[StirCrazy]

Most bulbs I have found are rated at two different bulb life, under 15 watts seam to be 6000h or 250 days 24/7, the over 15 watters seam to be about 8000 hours so 333 days. I had a 23 watt bulb and I did a once a year bulb replacment, and I replaced it in the spring, so it was most effective during the higher temp weather when algae blooms would be more frequent.

Steve

[Delphinus]

Hmm interesting. I seem to recall the number 8000 hours somewhere in the documentation which I was just too lazy to look at last night, so I'll dig it up and read it again later. But either way sounds like the replacement is due nonetheless. I still just find it sort of odd that it seems dimmer after I unplugged it but I can't be sure if I'm just imagining it or not. Luckily every part of it is replaceable including the power supply, but there are no local dealers whatsoever for AquaUV and even pestering the distributors around here (Hi Nate :p) didn't yield a local supply for that brand, so it's all mail-order. I'd just hate to find out that I should have ALSO ordered a replacement power supply but the odds are just better that it's just the lamp and there's no reason not to be optimistic that this is all it is. Thanks for your comments... Off to go order me a new lamp. Helloooooo Champion Lighting, it's been a few months, how ya doing! You're looking fine I must say. :mrgreen:

[sphelps]

Yeah manufacturers will likely state longer bulb life just like 12 months for Halides and 18 months for T5s which isn't the case if you want to keep your par levels up.

[Delphinus]

True dat... thanks. :)

[StirCrazy]

Yeah manufacturers will likely state longer bulb life just like 12 months for Halides and 18 months for T5s which isn't the case if you want to keep your par levels up.

that depends a lot on the type/brand of bulb and the ballast it is run on.

I know that AB10K SE run on a M80 ballast will only lose about 15% in two years.

Steve