Bulb life of T5 HO's?

[Roddy]

I am noticing a lot of stretch in my gals as opposed to grows before. Some of this could simply be strain etc, but other than this, the lights are the same, the distance from lights are the same and all conditions are similar. I suppose t could be due to a switch in nutes, causing them to grow differently, but am leaning more toward the bulbs getting weaker? What would be a normal bulb life and do they diminish is strength as they wear?

I'm not opposed to replacing bulbs as often as needed, just need to know whaen that is lol

 

[maineharvest]

Ive recently replaced two of my T5 bulbs and when looking at the light plugged in, it is obvious which bulbs are the new ones. They are much brighter. I have also noticed that the last two inches on both ends of the older bulbs have burned out and are not really putting out much light. I am going to the shop this week to replace my last two bulbs. They are nine dollars apiece for a decent brand bulb. I cant remember the name of the brand though.

 

[Mutt]

I see the guys on the reef tank sites push it to 12 months without much par loss. they claim 18 months. reef tanks is similar to our needs of veg for weed. So 10-12 months swap em out.

 

[maineharvest]

My bulbs were a few years old but used off and on. So about a year sounds good to me.

 

[Roddy]

Must be something besides the lights then, THANKS!!!!