I replace my lamps ever year. If you have many lamps, you can just write the exp. date on the lamp to keep track of them. I dont toss them, I just use the 1yr+ lamps on my germination beds, for heat or in the garage.

Keriann~

On the box the lamps come in they list the expected useful life. The Phillips Altos I use have an expected useful life of 30,000 hours if I remember correctly, which means they should last about 15 years or more depending upon how much you run them. I am using bulbs I bought 15 years ago. Replacing bulbs needlessly is a waste of money and bad for the environment.

I toss them when they start flickering or burn out. Even at 16 hours a day 365 days a year that's over 5 years if they've got 30,000 hours on them. Granted my fixtures are overdriven but I can use bulbs that don't work anymore in regular fixtures. The extra power will fire the gases when N.O.fixtures won't. Fluorescents only lose 5% of their efficiency over the first year and only up to 10% in their life time AFAIK.

Ya, use the lamps longer, they barely lose any lumens or efficiency even after years of use. You can swap them out but do not throw out fluorescent bulbs till they start flickering or stop working.

I use the 4ft 40watt T-8 lamps and they last for years without losing any punch. But if one goes out I replace both bulbs. I have this 5ft square closet that I have made into my little nursery for years now.

my setup
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