[HotRodx10]

I have never had to flush any toilet more than once. I just make sure the tank fills sufficiently.

That would be my first thing to check.

 

[HotRodx10]

Have you checked yet to see whether the tanks refill all the way up to the fill line on the inside of the tank, and that they empty at least most of the way when it they're flushed? If all it takes is dumping water in the bowl to make them flush properly, maybe they're just not getting enough water from the regular flush.