Brett......I believe Jeremy at PA (my lighting guru) suggests simply changing all of them at once and don't bother fuses with reduced photo-period, etc.
BTW: I give you credit.....I can't seem to jump to the darside (no pun intended) regarding switching from Radiums. Just too many sps growers out there that have great success, especially many TOTM guys. But, Sanjay runs Ushiro's and GREAT results too.
Will follow your experiences very closely becuase I am due to a bulb change within the next month or so. Did a Google search and can get 250w Radiums for $70/ea. delivered.....if in stock

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