I know I am a sucker. Hey I order more and just get new ones. Don't know. Think all merc vapors are finicky. They are all hand made I guess. Leads to more bad bulbs. Hmm maybe I should go get 5 4 ft zoomed bulbs and plain old flood bulbs from home depot. Instead of 9 merc vapors. Maybe that is what I will do. Not sure. Will need another rack soon. Maybe try this idea on the new rack and see how it works. 9 merc vapors are expensive.