Single-flush toilets: A low-flow single-flush toilet that uses 1.6 gallons per flush won’t save as much water (or money) as a ...

And even in their liquid-waste setting, dual-flush toilets save little water over a capable, single-flush toilet—and can use far more if they require a second flush to completely clear the bowl.

It makes for a cleaner flush that uses less water. Pressure-assist toilets depend on water pressure to recharge, so they don’t work well in homes with low water pressure. A toilet with a dual ...