Fluorescent shop light.....T8 vs T12....interchangeable?

[Norminn]

Bought a shop light, two bulb T8 for garden seedlings (indoors, of course). The clerk told me that T12 bulbs will fit it, so I bought them. It was an old guy and I figured he might know more than the package instructions disclosed.....haven't opened the packaging yet, and I suspect I should go back and get T8 bulbs. I don't know the peculiarities of fluorescent bulbs/fixtures. Can I use the bulbs or do I exchange them for T8?

[John Grabowski]

*It's not likely that the ballast will have a dual rating for T8 and T12. Get rid of the T12's and use the T8's. I think the manufacturing of T12's has stopped by now.

[philoÂÂ]

They might fit OK but would require a different ballast transformer.

You do not want the old technology, go back and exchange them for the T8's