What other pets should be avoided if you have a cat?

Those python from southeast Asia are HUGE. They are known to swallow American alligator whole. Of course they might eat a cat if they think it isn't too small of a meal.

With large aquariums, I would more worry about the cat might drown in there. Think about those tall tanks. If the cat jumps onto the top of the tank and try to get at the fish, or simply lost foot, I have a hard time to imagine the cat can get out of the tank once falling into it.

I had actually seen a video of a cat tried to bother a large fish. It ended up that large fish was fed up with the cat and grabbed the cat by the leg and pulled the cat down into the fish tank. The cat drowned.