Toilet floats are used to maintain the water level in a toilet tank. The toilet float is made of hollow plastic and floats (hence the name) on the surface of the water. As the water in the tank rises, it carries the float with it. When the float reaches a certain level, it cuts off the fill valve, which shuts off the water supply to the tank. If your toilet isn't flushing like you think it should, adjust the toilet float so your tank fills with more or less water.
Remove the tank lid. Set aside.
Locate the toilet float and determine which type you have. The float is a large, plastic device that floats on the surface of the water. They are typically coloured black or beige. The two major float types are the ball bloat, which is about the size of a softball and connected to a float road, and the integrated float assembly, which is ring shaped and positioned around the fill valve on the side of the tank.
Adjust the ball float type by bending the metal rod that connects the float to the fill valve. Bend the rod down to lower the water level in the tank, bend it upward to increase the water level. Newer ball float types may also have a screw at the end where they are attached to the fill valve for adjustment. These are usually turned to the right to lower the tank level and to the left to raise the level.
Adjust an integrated float assembly by turning the adjustment screw located at the top of the fill valve. These are turned to the right to decrease the tank water level, and turned to the left to increase the level.
Flush the toilet after you have made the adjustments. The tank will fill to the new, adjusted level and cut off at the appropriate spot. If needed, make further adjustments, flushing to check your work.
Replace the tank lid.