If your toilet was made before 1994, it's likely using way too much water &mdash because of the National Energy Policy Act of 1992, any toilet made after 1994 has maximum flush limit of 1.6 gallons per flush. But dual-flush toilets can do even better than that, giving you the ability to use half that limit for a 'light' flush. Upgrading your toilet to reduce your water usage can be as easy and inexpensive as buying a $30 retrofit kit, or as fancy as a several hundred dollar floating wall mounted modern toilet. The choice is yours, but check out a few of our recommendations after the jump.

When shopping for efficient toilets, look for ones that are marked with the WaterSense label &mdash these are toilets that are certified by independent laboratory testing to meet rigorous criteria for both performance and efficiency and only toilets that complete the third-party certification process can earn the WaterSense label.

1. HydroRight Dual Flush Toilet Converter by MJSI, $30: The HydroRight is a conversion kit for your existing toilet. It replaces your flapper with the HydroRight converter and provides you with a split button: Small (for quick flush liquid & light waste removal) and Large (for full flush solid waste removal). While some of comments said it does indeed save water, the kit is a little difficult to install and the push buttons are lacking in quality.
2. Simple Flush by Brondell, $79: Previously known as Perfect Flush, the Simple Flush by Brondell is another conversion kit that claims to reduce water use by 30-40%. The interesting feature is that both the 'half' and 'full' flush volumes can be adjusted with a dial to customize to your needs.
3. WaterRidge, $199: Found at Costco, this is one of the least expensive dual-flush toilets we've featured on Re-Nest. The drawbacks we found though is it does use more water and has a less effective flush than other dual flush toilets brands.

4. Caroma Sydney Toilet, $319: Caroma makes some of the best dual-flush toilets in the industry. Heather over at AT: Chicago bought this toilet from Green Depot (formerly Greenmaker) and couldn't be happier with the upgrade.
5. TOTO WaterSense Aquia Series, $300-$475 (depending on model color from Amazon): TOTO makes some of the best and dependable water efficient toilets.
6. Caroma Caravelle One-Piece, $352: High efficiency, clean lined and WaterSense certified.
7. Kohler Persuade, $478: The Persuade is a WaterSense labeled two-piece modern and compact design.

8. Caroma Profile Smart, $480-600: This space saving toilet not only uses less water than other dual flush toilets (only 1.28 for the 'heavy'), but it has an integrated sink, which directs it's waste water into the toilet tank for gray water reuse.
9. Duravit Starck Toilets, $739.25 (including the Geberit in-wall carrier from Amazon): This toilet is so sleek and awesome; it performs really well and the tank hides in the wall for a very clean and modern look.
10. Kohler Escale, $1076: Kohler's Escale line is their super modern and contemporary collection of plumbing fixtures. This toilet is WaterSense labeled and uses .8 gallons for the light, 1.6 for the heavy flush.

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