Lifespan of T5s?

[d3rryc]

What's the expected lifespan of a T5 bulb? My light rig has six bulbs, two of which are actinic. The actinics run 7AM - 9PM, and the other four run 8AM - 8PM. They are not being overdriven to my knowledge (although I need to confirm that). The reason I ask is that I've got a few corals that are bleaching a little, and I can't find a chemical reason to explain it. I read something recently on RC saying it might be possible that my bulbs were getting too old and creating problems for the zoozanthellae, which would result in bleaching. Any thoughts?

[Gseclipse02]

how old are the bulbs in the unit ??

[jc]

I read from one post that overdriven bulbs should be changed every 6 months. So if you don't overdrive then you get at least 6 months.

[alton]

Safe bet is 12 months. Now is a good time to buy a light meter so you know exactly when to change. Because it could be 8 months or they could last longer than 1 year. I run my MH around 18 months checking monthly with a light meter

[d3rryc]

Bulbs are probably almost 18 months old. I'm starting to doubt the manufacturers' claim that T5 bulbs only degrade about 10%... ; ) Would the drop in output account for the bleaching I'm seeing from a couple of corals?

[Gseclipse02]

i would think so put any sps under poor lighting and it turns white .... well this happened to me when frags fall under rocks same theory i think

[Gseclipse02]

I read from one post that overdriven bulbs should be changed every 6 months. So if you don't overdrive then you get at least 6 months.

i heard it was 6 months for PC lights

[cpreefguy]

Overdriven T5s will need to be replaced about 3x as often as T5s not being overdriven.
So about 6 months for overdriven, and 18 months for non-overdriven.

[alton]

8 months to a year for CFL's.

[labrown]

What do you mean by being overdriven?