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Compatible Toilet Tanks: System-based Replacement Guide

Toilet tank replacement, will you do if your tank cracks or is damaged? Contrary to the toilet bowl, toilet tanks require replacement because they are constantly working. They’re responsible for flushing the water down your toilet.

Often, the tank might have issues like not filling up or leaks, raising the need to replace it. The question is, how do you choose the correct tank for your toilet? Are toilet tanks universal? No, toilet tanks aren’t versatile. However, they vary in size depending on your toilet’s flushing system categories unless you have a customized bathroom. 

To better understand this particular topic, ensure you read this article to the end.

Are Toilet Tanks Universal? Answered

Toilet tank replacement

No, toilet tanks are not uniform. However, they can be universal in the same flushing system categories. Toilets come in three flushing systems: 

  • Dual flushing
  • Gravity
  • Pressure-assisted

Therefore, toilets within a dual flushing system have a universal tank size, like the other categories. As a result, knowing your toilet’s system category is essential to having a successful lavatory tank replacement. 

Overall, after knowing the flushing system of your toilet, you can go for any toilet tank in that category. That ushers us to our next subtopic. Let’s dive right into the details.

Types of Toilet Tanks Based On the Flushing Systems

To replace your tank, you should ensure that it aligns with your toilet unit, as a mismatch could ruin your plumbing or lead to a malfunction. Listed below are three common toilet appliances available to users. 

The Gravity Flush Tank

Gravity toilets are the most commonly used toilets in many homes. Like their name, they flush using gravity, thus enabling water from the bowl to the sewer line. Usually, they’re cheaper compared to their counterparts in the market.

The Pressure-Assisted Tank

Its design is similar to that of a gravity toilet. However, it differs as it uses pressure from the tank to push the water down the pipe into the bow. The pressure created is responsible for releasing the water after the handle is pressed and eventually through the sewer.

The benefit of these toilet tanks is the high pressure pushing the waste further, contrary to gravity system tanks.

Dual Flush Tank

It is a dual-button flushing mechanism found on the top of the tank controlling the amount of water used to flush the toilet, whether more or less. The more prominent button permits more water, while the smaller button flushes less water, making it eco-friendly and effective. In addition, it also saves you from high bills as there is minimal water wastage.

Nevertheless, if your toilet is a dual flushing model, ensure that you get a compatible tank when shopping for a replacement. But how will you know they’re compatible? If the toilet and the tank are similar and have exact dimensions, they will match.

Are You Stuck On The Tank You Need? Solved

First, know your toilet brand by looking at the inner side of the tank or down right behind the bowl.

Next, check on the serial number, which probably may be inside the toilet tank.

You can either Google it for a recent toilet model, if successful, order your replacement parts online. Alternatively, you can go to your local hardware or improvement store and request them to find the right replacement tank for your particular toilet.

What Are The Different Toilet Tank Sizes?

Knowing the type of your toilet’s flushing system is crucial, but take extra measures to ensure everything fits well. Here are the critical measurements you need to make 

  • Depth of the tank
  • The width of the tank ( is the length from the wall to the front of the tank)
  • The size of the tank (small tanks 151/8 inches and more giant tanks 163/4inches- 18 inches)
  • The pipes and fixtures 

The proper measurements are essential if you want to be 100% sure that you’ve chosen the appropriate tank size. Consider the space between the toilet bowl and the waste pipe. Your toilet measurements matter too.

10 Quick Steps to Replace Your Toilet Tank

Toilet tank replacement

Most people overlook the essence of the toilet tank until it starts to leak. Residential toilets comprise two parts-tank and the bowl. Unfortunately, if the toilet tank cracks, you have no choice but to replace it. 

You can do this without calling a plumber, as you can buy them separately. All you need to ensure is that the toilet and the tank match to ensure smooth installation and functionality of the appliance when done.

Here is a step-by-step guide on how you can install your toilet tank:


  • Towel
  • Adjustable
  • Screwdriver

First, cut off the water supply to the toilet via the water valve that extends from the floor behind the tank.

Second, flush the toilet to remove all the water from the bowl and the tank. With the remaining amount, use a sponge or towel to soak up the remaining water.

Third, remove the tank lid and loosen the nuts on the bolts that fasten the tank to the bowl using an adjustable wrench.

Fourth, lift the cracked tank gently from the bowl and put it aside.

Fifth, if your tank doesn’t have an already installed rubber gasket, install it into the opening at the new tank’s bottom.

Sixth, set the new tank in place, aligning the mounting holes in the tank with the holes in the bowl.

Seventh, slide the rubber washer over each mounting bolt and insert them into the tank from the inside. Note that the rubber washer goes inside the tank while the metal washer and nut go on the end of the bolt. If your new tank lacks these parts, reuse the old bolts or buy them from the hardware near you.

Eighth, slide the metal washer over the bolts’ end from behind the bowl and turn the bolts onto the nuts.

Ninth, insert a screwdriver into the bolt from the inside and hold the nut with an adjustable wrench. Turn the screwdriver to tighten. However, don’t over-tighten it, as you may crack the bowl or your new tank. 

Lastly, turn on the water supply, and flush the toilet to fill the tank and the bowl. Confirm that there are no leaks.

Conclusively, toilet tank replacement can be frustrating, but if the rest of the toilet is still in good condition, then it is worth it. However, it is paramount to know that toilet tanks are not universal. Nonetheless, checking your tank model and serial number is crucial to avoid choosing an incompatible tank. Also, it is good to take measurements of your tank before purchasing a new one.