Sometimes you can hear the toilet running. There are also leaks that are considered silent toilet leaks. Here are two visual tests that you can do to help you check your toilet for a leak.
1. Dye Test – Flush the toilet and wait 5 minutes for it to refill. Put a few drops of food coloring in the back of the toilet tank. Wait about an hour and do not flush. If the food coloring is now in the bowl of the toilet you will need to check, and in most cases, replace the plunger and seam in the toilet tank.
2. Stand tube test – Flush the toilet and wait 5 minutes for it to refill. Remove the back of the toilet tank cover. Sprinkle some powder on the top of the water. If the water level is too high, you will see the powder on top of the water drain down into the stand tube. This is a silent type leak in your toilet. You will need to adjust the water level to ½ inch below the stand tube.