Bulb Replacement Schedule?

I'm running 40w CFLs and a 430W HPS. My local hydro shop says the HPS should last about 2 years. So here's the question.

Should I wait for bulbs to fail before replacing them? How can you tell when a HPS bulb has gone bad? Does it just not turn on or does it glow dim? Same for CFLs? Do they start glowing dim or flickering and how long should they last?

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And oh yeah, my local hydro shop is closed two days a week. So if I blew a HPS , could flowering deal with darkness for 72 hours until I could get a replacement bulb? Also, do ballasts ever go bad?

they lose efficiency and lumens gradually

You can use a light meter to measure the lumens produced by your lights. Don't wait for the lights to blow out. The standard rule in growing is ... things will go wrong on Sundays and Holidays when the hydro store is closed. Your best bet is to keep spares of everything on hand.

Vi

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Grow Marijuana FAQ, Cannabis cultivation - marijuana growing tips & photos

You guys are all awesome! Answered all the questions and more in four responses.

So, I replace on schedule and I stock spares for everything. Costly but I'm sure it will keep the stress down. It always feels good to have a spare in the trunk.

Yeah, and if your hps did go out, put some kind of light in there, floro, cfl, whatever to keep the cycle going.

i run 6 4' flo strips off a seperate ciruit just incase the big ones go out.

Bulbs are cheap when in doupt always replace. i change one time a year. Dont want to be robbed of any lumens!! peaCE OUT

:wvguy are you running warm FLs for the flowering room as your backup?