There are two things that most people don’t know about their toilet which can actually save you a little bit of trouble. These two things have to do with the two screws on top of the ballcock. The ballcock is the long tube that is to the left of the tube in the middle of the tank.
The first screw is usually metal and is located near the rod coming out of the ballcock. This screw controls how quickly the tank fills up. A clockwise twist slows down the water and counter clock-wise lets the water in faster. You may ask, why do I care how fast the tank fills up? Mainly this is to do with noise. If the running water noise is too loud, then give the screw a twist and your toilet will be quieter. Never deal with a loud noisy toilet again!
The second screw is generally a larger plastic screw. This screw is located right in the center on top of the ballcock. It controls the water level inside of the tank. Most people resort to bending the float rod to adjust the water level often leading to inconsistent results or even a broken float rod. A simple turn of this screw will adjust the float level.