Thanks to the investors who sold me my current condo, I have the new water-saver toilets. Newer toilets have small tanks. There’s nothing gained by putting something in the tank to cause it to use less water per flush.
Pre-1995 toilets usually have larger tanks, so putting something in the tank to make it hold less will save water. The advice used to be to use a brick. Now they say bricks may fall apart and damage the mechanism. So if you use a brick, seal it up in a Ziploc bag. Or, maybe use a plastic container full of water, in a shape that suits your tank and won’t block the mechanism. You can weight it with pebbles or sand so it won’t float around.
There are also adjustable flappers available now that let you set the flush volume. I recently learned about a thing called a toilet fill cycle diverter. It stops older toilets from wasting water during the refill phase. You can get one from, among other places, http://www.niag ara conservation.com and www.nextag.com.
The old saying, “If it’s yellow let it mellow, if it’s brown, flush it down” would cut the water used for toilet flushing to probably less than half.
Some articles say to put a dye tablet in the toilet tank to check if the tank leaks into the bowl, wasting water. You can do this with food coloring just as well. Put a few drops in the tank. Don’t flush for fifteen to twenty minutes, and look to see if the water in the bowl takes on color. If it does, it may be time to replace the flapper that closes the hole through which water goes from the tank to the bowl.
Or, the chain may be lodging under the edge of the flapper, or maybe it’s too short and the flapper can’t go all the way down. There might be debris or hard water build up around the edge where the flapper sits. On my own experience, replacing the flapper and making sure the chain is the right length have always fixed it.