When Should I Change My T5 Bulbs?

[craigybaby37]

Its comming upto 6 months since ive had my T5 light fixture running and someone i know seems to recon its advised to change T5 bulbs every 6 months is thast right???

 

[DarrenUnwin]

Its comming upto 6 months since ive had my T5 light fixture running and someone i know seems to recon its advised to change T5 bulbs every 6 months is thast right???

My LFS has always suggested I change my T5 every 6 months. He knows I dont always purchase from him so I think its genuine. I beleieve its something to do with the spectrum of light it produces reduces over time, but I'm no expert in light mechanics

 

[Musho3210]

Its comming upto 6 months since ive had my T5 light fixture running and someone i know seems to recon its advised to change T5 bulbs every 6 months is thast right???

My LFS has always suggested I change my T5 every 6 months. He knows I dont always purchase from him so I think its genuine. I beleieve its something to do with the spectrum of light it produces reduces over time, but I'm no expert in light mechanics

i believe you have the wrong idea, its because you don't always purchase from him, he may lie to make money, which he sorta has here.

In reality, you can probably last 2 years before a replacement.

 

[n3ont3tra]

It depends on how long the photoperiod is.

 

[Colin_T]

It also depends on how warm the globes get. Globes that are in hoods or housings with little air flow become quite hot and die sooner. Globes that have plenty of air moving around them and are kept cooler will last much longer.
Over time the globes temperature or Kelvin (K) rating decreases. If you start off with globes that have a 10,000K rating then after 6 months they will only be producing about 8,000K. This is still fine for corals and plants. By the time the globes are 12 months old they are usually only producing about half of their original spectrum and intensity.
This is under average conditions and as mentioned if the globes are kept cooler they will last longer and deteriorate slower.
I usually recommend replacing halides or fluoros every 12 months under average conditions and every 6 months if they run hot, (ie: are in an enclosed hood).
A simple way to check is to put a new globe in the unit and see how bright it is compared to an older globe. Old globes also start to get black around the ends. This means they are on their way out.
When you replace globes you should also replace the starters.

 

[rhysiboy]

ive had my power compact bubls for 18 months now, aint changed them and i still get coral growth!

 

[SkiFletch]

It also depends on the ballast used assuming a typical 8-10 hour photoperiod. If your bulbs are overdriven they will burn out quickly at which point I'd reccomend somewhere between 6-18 months between replacement. Overdriven bulbs can diminish 20% of their PAR output in a year quite easily. Normally driven bulbs can last 2 years for sure before they get to around 20% loss in PAR and will need replacing. Also as Colin mentioned, overheating bulbs will burn through their phosphors faster and of course need replacing faster.