Regarding “half flush” toilets. Yes, these do exist and Caroma toilets make it pretty clear which button to press for the half flush, as they have 2 seperate buttons.

Toilets account for approx. 30% of water used indoors. By installing a Dual Flush toilet you can save between 40% and 70% of drinking water being flushed down the toilet, depending how old the toilet is you are going to replace.
If you are serious about saving water, want a toilet that really works and is affordable, I would highly recommend a Caroma Dual Flush toilet. Caroma toilets offer a patented dual flush technology consisting of a 0.8 Gal flush for liquid waste and a 1.6 Gal flush for solids. On an average of 5 uses a day (4 liquid/ 1 solid) a Caroma Dual Flush toilet uses an average of 0.96 gallons per flush. The new Sydney Smart uses only 1.28 and 0.8 gpf, that is an average of 0.89 gallons per flush. This is the lowest water consumption of any toilet available in the US. Caroma, an Australian company set the standard by giving the world its first successful two button dual flush system in the nineteen eighties and has since perfected the technology. Also, with a full 3.5″ trapway, these toilets virtually never clog. All of Caroma’s toilets are on the list of WaterSense labeled HET’s http://www.epa.gov/watersense/pp/find_het.htm and also qualify for several toilet rebate programs available in the US. Please visit my blog http://pottygirl.wordpress.com/2008/08/01/what-you-should-know-about-toilets/ to learn more or go to http://www.caromausa.com to learn where you can find Caroma toilets locally. Visit http://www.ecotransitions.com/howto.asp to see how we flush potatoes with 0.8 gallons of water, meant for liquids only. Best regards, Andrea Paulinelli