I've found that any powdered detergent is quite good for scrubbing out the tub (or even the toilet for that matter). However, try adding a small bit of baking soda along with the detergent. It'll really get it clean!
. . . a/k/a/ Jan Miner was fluent in every major European language and so capable of convincingly delivering the lines phonetically in other languages that she appeared in nearly all the international versions of the Palmolive spots. Only the Mandarin Chinese commercials needed to be dubbed. In Australia and New Zealand, "Madge" was played by Robina Beard.