How to Adjust the Water Tank Level in a Toto Toilet

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You can adjust the water level in your toilet tank.
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Like anything else, a Toto toilet can have occasional issues. After all, toilets are a frequently used appliance within the household, and even the most impressive will see a decline in function as time passes. One issue they might experience is a change in water level. Fortunately, adjusting the water level is fairly straightforward and requires few tools.


More About Toto Toilets

Toto toilets are known as expensive, top-of-the-line, well-designed appliances that often contain luxury features that aren't found in standard toilets. They have advantages over their competitors, including a more powerful flush, quieter flushing and refilling noise, and normally less need for maintenance as compared to other standard brands.

In addition, Toto has developed efficient water-saving technology to help lower water usage. The top Toto toilets can even offer heated seats, bidets and automatic open-and-close lids. They are pricier but make a great investment for homeowners looking for a model that will last more than 10 years.


Over time, the water level in the tank may drift away from the marking on the inside of the tank. This can happen for a number of reasons: A slow leak can cause the level to lower over time, and changing water pressure might cause the level to need a readjustment. If the level in the tank is too low, the flush will not be as thorough, which can affect the way the bowl rinses.

How to Change Water Levels

Before adjusting the water level equipment, be sure to check the flush mechanism and troubleshoot it for issues. Cracks or wear in the rubber of the seal at the bottom can cause water to leak into the bowl, making the toilet run and potentially decreasing the water level in the tank.


Problems with the chain connecting the flush valve and the ball can also cause flushes to be interrupted or otherwise changed. Make sure the mechanism is in good shape and working correctly; if not, be sure to replace it before moving on to adjusting the water level. In many newer Toto toilets, the flush mechanism has been upgraded to be more straightforward and robust.

To adjust the level of water in the tank, ensure that water to the toilet is turned off by closing the valve situated below and behind it. Then allow the residual water to drain by flushing the toilet. The tank should not refill; if it does, the water valve is leaking.


Troubleshooting the Issue

Inside the tank is the flush valve, a cylindrical tube mounted vertically inside the tank. Turn the tube counterclockwise about half a turn to unlock it.

Then, adjust the flush tube to change the water level as desired. There should be a marking on the tube to indicate the water level; you may want to measure the height of this mark before and after adjustment. Once the tube has been relocated, turn it clockwise about half a turn to lock it back in place.


Once back in place, open up the water supply and allow the tank to fill. Check the level in the tank. Flush at least once to check the refill of the tank and verify the water level is reaching the desired point. Keep an eye on the equipment within the tank and check periodically for buildup, aging or damage to keep your toilet working at its peak efficiency.


references & resources

Danielle Smyth is a writer and content marketer from upstate New York. She holds a Master of Science in Publishing from Pace University. She owns her own content marketing agency, Wordsmyth Creative Content Marketing, and she enjoys writing home and DIY articles and blogs for clients in a variety of related industries. She also runs her own lifestyle blog, Sweet Frivolity.