How to Adjust the Water Level in Your Toilet Tank

The inside of a toilet tank
What You'll Need
Float Ball
Petroleum Jelly
Plumbers Tape
Screw Driver
A Small Brush

The water in the toilet tank is used to flush the toilet bowl. When the toilet bowl does not get cleaned while flushing, the water fill level in the toilet tank should be increased. If you feel the need to conserve water, you may choose to reduce the water level. A float is fitted inside the toilet tank in order to control this level. When the tank begins to refill after flushing, the flow of water into it stops automatically according to a preset level. This is because the float gets lifted by the buoyancy of the rising water, and it closes the water valve through which the water enters the tank. Here’s how to make adjustments to that water level.

Water Level Too High

Step 1 - When the float ball is too high, it allows the water to leak into the overflow pipe. To fix this, bend the float arm slightly to keep the water level to an inch below the top of the overflow pipe. Check that enough water reaches the toilet bowl by flushing it. If it does not flush properly, adjust the float ball slightly until you get the proper water pressure needed to flush the toilet.

Step 2 - A damaged float ball will not rise to close the ball cock through which the water flows in. Using pliers, grasp the float arm and screw off the float ball counter clockwise. Apply plumber’s tape or petroleum jelly to the float arm threads before placing a new float ball.

Water-Intake Assembly

inside a toilet tank

Step 1 - If your toilet has a water-intake assembly instead of a float ball, pinch the clip attached to the thin metal rod.

Step 2 - Slide the rod and the attached cup down to lower the water level.

Step 3 - To increase the water level, slide the clip with the cup upwards. Take care to move the clip about an inch at a time either way.

Metered Fill Valve

Step 1 - If the tank has a metered fill valve instead of a float, adjust the water level using a screwdriver to turn the knob counter clockwise, and lower the water level.

Step 2 - Turn the knob clockwise to increase the water level. Take care to turn the knob only half way at a time.

Ball Cock

ballcock inside a toilet tank

The ball cock opens and closes according to the rise and fall of the float balls and controls the water flow into the tank. The float arm pushes the valve plunger and washer to stop the water flow in the plunger-style ball cock. If it is a diaphragm-type ball cock, the plunger pushes against the rubber diaphragm.

Step 1 - Turn off the water connection to the toilet and flush it.

Step 2 - Slide the float arm out of the way so that you can reach the assembly. Remove the screws around the ball cock assembly to reach the washers or diaphragm. Use a small screwdriver to remove the washers from the valve plunger.

Step 3 - Clean the sediment inside the ball cock and the washer with some vinegar and a small brush.

Step 4 - Reassemble the parts after cleaning. If the problem persists even after that, replace the ball cock.