The flush valve on today's toilets operates on a water intake system that allows the float to ride up and down a metal rod in the toilet tank rather than have a large float ball. Increasing the water level provides a cleaner toilet with more water going down with each flush. The valve can be adjusted to decrease the water level in the tank to conserve water. The toilet flush valve determines how full the toilet tank will be and can be adjusted to eliminate leaks.
Lift the toilet tank lid off the tank and set aside.
Locate the metal rod on the side of the water intake assembly.
Pinch the clip on the rod and slide the float cup up the metal shaft to increase the water level in the tank. Slide the float cup down the shaft to decrease the water level in the tank. Release the clip when the float cup is positioned to the desired level.
Replace the toilet tank lid onto the toilet.