Came in too late to look smart and answer the question, but I do have a bit extra info. Tourists visiting places on the equator will often be persuaded to part with money by locals claiming to show the coriolis effect on water going down plug-holes. They show the water going different ways depending on which side of the equator they are standing. They actually produce the effect by the way they fill the bowl with water and the touristsfall for it.

However I don't begrudge an entertaining con-man, so don't blow his cover if you are ever there.

Bagpuss