how often should you change bulbs?

[c_bell]

I'm running NO fluorescent tubes on my 46 gal bow front, and I was wondering how often I should switch out the bulbs. The reason I am asking is because the tank has been set up for about 7 months with the same tubes and im noticing some diatom blooms. I always use RO/DI water for water changes and tops offs, and amm 0, trites 0, trates 10 ppm. So I figured its time to switch out the lights, is it???

 

[gatorcsm]

Usually you can get 12-18 months out of bulbs. 12 months should keep optimal output.

 

[ruaround]

Although the tubes may last for over a year, the red spectrum actually starts to jump in the 6th or 7th month. IMO you should change NO bulbs every 5 to 6 months. If you are noticing a diatom bloom, and havent changed your bulbs for 7 months change em. HTH.

 

[barracuda]

NO Fluorescent ideally should be replaced every half a year, especially actinics, but may be replaced after 1 year of service. It also depends on how much hours the particular lamp was on. If you run your bulbs with timers so that several lamps are on for 12 hours and some only for six hours (for example), so lamps that run only 6 hours a day maybe replaced later.

 

[cadbury]

I was told every 6 to 8 months as well for optimal results.

 

[kpogue]

Where might this study be? IME there is a very noticable change in my lights after about 9+mos. I use URI VHO's for my actinics.

 

[kpogue]

ok...sounds good.