JasonandSarah
Non-member
Yeah I would say at least 10 months safely. I know people that don't change them till they burn out. But that's not a great thing to do.I am using new/different bulbs, so I'm sure the spectrum changed, but that's not why I got new bulbs. I thought 7 months was pushing it for the life-span based on what I'd heard. Guess I will swap them back for another 4-5 months and hold on to the new ones.