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Conservation Crafts DIY Toilet Tank Displacement Device

DIY toilet tank displacement device

A Porcelain Problem

Ah, the toilet. Considered by many to be essential to our daily lives, toilets are a common feature in Sarasota County homes. We use them daily for our private business, sometimes upwards of 10 times a day. In older toilets, each of those flushes amounts to an average of 3.5 gallons lost. Newer toilets use less with an average of 1.6 gallons per flush. However, no matter the age, each porcelain throne has the potential to use up dozens of gallons a day.

There are a few notable ways to save water in the restroom. First of all, you can (and should) check your toilets for leaks. A leaking toilet can waste an average of 200 gallons in just one day. You can also follow the age old saying, “If it’s yellow, let it mellow.” Sure – that will save you a few gallons. We certainly aren’t knocking it. That said, what if we told you there’s a way to save up to 40% of water each time you flush?

Say hello to the fun and easy to assemble toilet tank displacement device. A toilet tank displacement device is an object you place into your toilet tank to take up room. Less space in your tank means it takes less water to fill up, so you can save water with every flush.


Making your own toilet tank displacement device is both a rewarding and fun experience! It only requires two components, which are both inexpensive and easy to find. Essentially, the device consists of an outer container and a weighted filling. Given the availability of these items in your home, the craft itself should only take 5 minutes.

Step 1. Select Your Container

Step 1. Select your container

The container for your toilet tank displacement device should be both impermeable and durable. If water gets into your device through a hole, then it cannot properly displace the water in your tank. Additionally, it is important that it can withstand the force of multiple flushes throughout the day. Most toilet tanks are around 18″ inches tall, so try to find something 16″ inches or shorter. We recommend using what you already have, so here are some ideas for your device’s container:

  • Plastic water bottle
  • Resealable bag
  • Glass jar with lid
  • Empty ketchup bottle


Step 2. Fill Your Container

Step 2. Fill your container.

There are a number of things that could work here, but the key is to find something that will keep your toilet tank displacement device weighted. In order to work its best, the device must sit at the bottom of the tank. If it floats, then it will sit on top of the water instead of displacing it properly. See below for some filler ideas:

  • Aquarium gravel
  • Small rocks
  • Sand


Step 3. Open up Your Toilet Tank by Removing the Top Lid

Step 3. Open up your toilet tank by removing the top lid.

If you’re not used to performing maintenance on your toilet, the tank is the top part of your toilet that holds water between flushes. When you flush your toilet, the water from the tank will enter the bowl with enough force to push its contents down into your pipes and through our county’s sewage system. Every tank should have a removable lid. Once you find your lid, remove it and place it somewhere close by.

Step 4. Place the Device in Your Tank

Step 4. Place the device in your tank.

Now comes the easiest part! First, find the most open part of your tank. Make sure that there are no valves or seals that might be blocked. Then place your device so that it sits vertically, with the bottom of the container touching the bottom of the tank.

Step 5. Save up to 40% of Water with Every Flush

Step 5. Save up to 40% of water every time you flush.

Nice job! You did it. You assembled and deployed your very own toilet tank displacement device. Now it’s time to rake in those sweet water savings (and maybe take a few minutes to celebrate). Not only are you helping to conserve our valuable, freshwater supply, but you are also putting some extra money in your pocket each year. Way to go, Water Warrior!

If you’re looking for more ways to save water, check out our Water Conservation website:

An Equal Opportunity Institution. UF/IFAS Extension, University of Florida, Institute of Food and Agricultural Sciences, Tom Obreza, Interim Dean for UF/IFAS Extension. Sarasota County prohibits discrimination in all services, programs or activities. View the complete policy at

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