Toilet Tank Displacement


Introduction: Toilet Tank Displacement

Use less water per flush with this simple trick!

Step 1: Required Materials

You will need:
One (1) half-gallon plastic jug (one of the small, tall ones)

Step 2: Preparation

Fill up the bottle nearly to the top with water and cap it off. Then, take the top off of the toilet. It probably looks something like this:
(Wow, mine's kind of rusty. I should probably clean it...)

Step 3: Finale!

Flush the toilet!
Now, once most of the water is gone, put your water-filled jug in, in the corner, where it won't mess with the flushing parts.
Watch it fill up. The jug is now displacing some water, and as the tank fills, it reaches the float sooner, which stops the flow of water. Every time you flush, you will be using 1/2 a gallon less water. If you have room, you can even put in two or three of these, but then it may affect the amount of water in the bowl, which may not be good. Fiddle around with it!



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    This is a great Instructable, but you need to add a main image of the final project to the intro step. Please do that and leave me a message when you have so that we can publish your work. Thanks!

    1 reply

    Another thing you should do is adjust the fill valve to lower the water line.

    Good instructable! Although I agree with dchall8, as I have used a displaced toilet for a while, and eventually had to remove the displacement. The flow with a displacement leaves something to be desired, especially if you are regularly flushing a lot of solids. I had to plunge about 30% of the time to get said solids down the drain, and eventually got sick of it. I would agree it is just that much simpler and better to get a low flow toilet, one designed to specifically keep solid removal high, yet use less water. On another note, you could just use all the water you want with a regular toilet, but use a gray water input for recycle your used washing machine water. There are lots of instructables here on that topic, go see!

    Why not just bend the float arm so that the float doesn't have to go as high to close off the valve? Seems like it would do the same thing as this instructable, with no materials required at all, and it's infinitely variable.

    "Watering" your garden directly or indirectly saves 100% of the water which would otherwise be used in a flush. L

    1 reply

    Yeah but you cant feed a garden. lol

    Just to let you know, the toilet engineers have solved the problems with low flow toilets. The new models of toilets by American Standard, Kohler, Gerber, Eljer, and Crane are a lot better than even the old high volume toilets. Flush time is 3 seconds, refill is about 30 (depending on your water pressure), and flushed mass is up to 1 pound of solids. Older toilets took 12-18 seconds to flush, refilled in under a minute, and could often not flush more than 1/4 pound of solids. The new ones are quieter, too.