Leaks account for 12% of all water use in America, and it’s often the toilet that’s at fault. If you want to save on your water bill try this:
Remove the lid on the tank
Drip 10 drops of food coloring into the tank
Replace the lid
After 15 minutes, look in the bowl
Is the water in the bowl food-colored? If so, you’ve got a leak and need to replace the flapper.
Here’s how to fix it:
Turn off the water supply by turning the valve located behind the toilet
Remove the lid and flush
Mop out excess water with a sponge
Remove the chain from the lever
Slide the faulty flapper up and off the overflow tube.
Replace the flapper, re-hook the chain, turn on the water and test again