Changing Bulbs

[JM68]

I am changing all 4 of my VHO bulbs and i was wondering what is the best way to do it. Should i do two and two or should i change each one individually over the course of a week or two. The current bulbs that i am taking out are about 8 months old just so u have an idea of how far into their life they are. My original plan was to change two then wait about a week and change the other two. would that be ok?

ps bulbs are 46.5" 110W over a 120g

[JM68]

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