On the equator, toilets don't flush at all. People bury their waste in the yard.
It makes sense: To the people facing down from the North, the Earth moves in a counterclockwise direction, while to the people facing up from the South, the Earth is rotating clockwise, thus causing the water in their respective hemispheres to drain in the direction of their perceived rotation.
The Coriolis effect is totally a thing, and it really does affect the direction in which things spin. Like this:
Say, when you and your enemy exchange grenades on a merry-go-round.
But the sharper-eyed among you might have noticed that, in the diagram above, the object was relatively big in relation to the spinning disc. And that's the trick: In order for Coriolis force to have an effect on earthly phenomena, said phenomena have to be really big. So Coriolis force affects the direction in which hurricanes and cyclones spin, seeing as how those things are massive amalgamations of murderwind, but it doesn't affect your little toilet, no matter how murderish your personal wind may be.
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