Planted Tank Guru
Join Date: Jun 2004
Location: Baton Rouge, LA
When comparing incandescent to spiral fluorescent (CFL), use the actual wattage of the incandescent, and the "equivalent to" wattage of the CFL which is displayed on the package.
For example, a 23W CFL is "equivalent to" a 100W incandescent, a 13W CFL = a 60W incandescent, etc.
I recently saw some incredibly tiny CFLs at Lowe's. Smaller than any others I've seen, including the ones Wasserpest linked. Had to stare at them for a minute and say "wow", but I'm afraid I can't remember the brand.