how many

[blindside]

Hours do you leave your lights on? What times do they come on and off?

[seaurchin]

My 4x96w pc's kick on at 6am and shut off at 2pm. my2x65w pc's 10000k kick on at 8am and kick off at 5pm. I have 2x65w pc actinics I turn on manualy at 9am and off at 6pm.

[DrMark]

MH 1230pm to 9pm.
Actinics 1145am to 945pm

[Mr Cob]

Actinics: 2pm-12midnight (10 hours)
MH: 4-10pm (6 hours)
Refugium: Reverse lighting schedule 10 hours

[blindside]

I only have mh lights, and I keep them on from 9 to 9 after seeing all these schedules, it seems I keep them on too long?

[jrsatx20]

too long to run mh ur gonna have to replace them way before u should. that could be the problem with the ha

[medi]

How long do MH bulbs usually last?

[SoLiD]

I read somewhere on Reef Central that if you have some sort of active cooling such as a fan blowing across the bulb, you'll get about a year and a half on an 8 hour schedule. As with everything, it also depends on the bulb but the main thing is the daily burn time. I'd say a year to be on the safe side.

-David