For serious buildup use a pumice bar. At least that's what I think it is.
It looks like an enongated bar of stone but is softer than the toilet and
harder than the buildup so it doesn't hurt the toilet. It isn't meant for
regular use but does the job quickly.

Of course regular cleaning keeps the buildup from gaining a hold.

wrote in message
oups.com...
Has anyone used BKF for lime scale in a porcelain toilet bowl?

BKF says it can be used on sinks, baths, etc., but they don't mention
toilets.

Seems like it might be effective. We've had a problem and neither CLR
nor vinegar has not been helpful!

Any comments appreciated!