Check toilets for leaks 

Did you know one of the most common places for water leaks is inside your toilet? These leaks are easy to miss since the water trickles from the tank to the bowl and disappears down the drain.

To see if your toilet is leaking, place a few drops of food coloring in the toilet tank. Wait an hour or two without flushing. If you see color in the bowl, the toilet is leaking. Replacing the rubber flapper inside the tank will fix these slow leaks in most cases.