The latest low-flow toilets use even less water: California now requires that a residential toilet use 1.28 gallons per flush (gpf), 20 percent less than the 1.6-gpf standard in effect elsewhere nationwide.

The American Standard FloWise (shown) is among the first commodes to meet the new California standard without requiring a second, water-saving mode. It also carries the EPA's WaterSense label for high-efficiency toilets—€”akin to an Energy Star qualification—€”and is eligible for rebates in drought-prone areas.

This gravity-fed toilet is green without being wimpy, claims American Standard, thanks to a funnel-shaped, piston-action flush valve that helps accelerate incoming water; the valve is similar to the one on the company'€™s Champion models, a line of gravity toilet that did well in our last toilet report.

The FloWise retails for $395 in white and is backed by a 10-year limited warranty. We'll see how these American Standard models and other lower-flow toilets fare in our next toilet test.—€”Bob Markovich