You can fix this
Likely cause: a worn flapper
Color in the bowl means water is slipping past the flapper. A new flapper usually fixes it.
Why this happens
Korky says a worn flapper or flush valve seal lets water slowly leak from the tank into the bowl, and that replacing it will usually fix this kind of running toilet. EPA says an old or worn flapper can make a toilet flush on its own or silently leak thousands of gallons a year, and recommends replacing flappers at least every five years. An archived EPA fact sheet puts a running toilet at 200 gallons of water or more every day.
How to fix it
- Push down on the closed flapper with a stick or your hand. If the running stops, the flapper is the leak.
- Turn off the toilet's supply stop and flush to drain the tank.
- Unhook the old flapper from the ears of the overflow tube and the chain from the handle arm. Take it with you so you buy the same size; Korky notes standard flappers are 2 inches and large ones 3 inches.
- Install the new flapper per its package, clip the chain on with 1 to 2 links of slack, as Korky recommends, and turn the water back on.
- Flush a few times and repeat the dye test. Family Handyman estimates the job at less than $20 and an hour or less.
When to stop. If the toilet's supply stop will not close, do not force it. Close the main shutoff instead.
If this does not fix it, tell the plumber
- The dye test showed color in the bowl.
- Whether the flapper is the standard 2 inch or large 3 inch size.
- Whether you already replaced the flapper.
Build the full list: what to tell the plumber.
Start this troubleshooter over
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