I'm posting this in the "growing from seed" forum too, so sorry for any duplications...

I'm replacing my fluorescent light bulbs this year (what a pain!), and so far two of the *new* tubes have developed a blackish ring around the ends. (I think of the blackish end syndrome as related to an old tube.) One of those two new tubes flickered a lot and then went out.

The fixtures are cheap old shoplights, so I'm wondering if there's a chance the fixtures are somehow killing the new bulbs? Or are these just bad bulbs? (they're from Ace, for what it's worth...)

I've put two new tubes in to replace the two with the black ends to see what happens.

Any thoughts?

Thanks!