In article , sinister wrote
in part:

I couldn't really find a 48" 25W T12 online, so the guy at the light store
gave me a 48" T8 32W. Seems to work OK, though it flickers at a low rate
somewhat.

The low rate flicker usually fixes itself after a few to a dozen so
operating hours followed by a couple on/off cycles. If not, then you have
a bulb/ballast mismatch causing this and you need to have the bulb match
the ballast (and in this case I would change the ballast and not the bulb
- thankfully "big box" home centers tend to have good ballasts for
F32T8!).

- Don Klipstein )