How often to change bulbs?

[Todd]

I was wondering how often I should change my bulbs. I have 4x96 power compacts. They light my 150 gallon FOWLR. Also by changing the bulbs, will that help algae from growing.

 

[roka64]

I'm not sure, maybe 6-9 months and yes, if they get old, the spectrum of the light will change, possibly causing an algea outbreak.

 

[afishyonados]

If you are running your lights 8 hours a day, nine months is about right.
If you are running your lights 12 hours a day, it may be more like five or six months.
The duration of your photoperiod will determine the functional lifespan of your lights.

 

[melosu58]

I run mine 12 hrs a day and change every 6 months. I have VHO lights. And yes lights gone past their limit will cause algea growth.

 

[Devilishturtles]

I run mine 8-10 hours a day, change every 9-10 months.