Bladder Tank vs Pressure Tank: What’s the Difference?

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Water storage tanks play a vital role in many homes and industrial settings. They’re used to store water for various purposes, such as irrigation, drinking, and cleaning. The most common residential use of a water storage tank is to deliver pressurized water from a well to a plumbing system.

There are two main types of water storage tanks: water bladder tanks and water pressure tanks. While both of these types of tanks can store water, they have some important differences that you should be aware of.

We’ve shared everything you need to know about bladder tanks vs pressure tanks in this guide.

📌 Key Takeaways:

  • Bladder water tanks and pressure tanks both deliver pressurized water around a plumbing system, and are commonly used with well systems.
  • The biggest difference between a pressure tank and a bladder tank is design: a normal stainless steel pressure tank uses compressed air to send water out of the tank, while a bladder pressure tank uses a rubber diaphragm to separate the water from the tank.
  • Bladder tanks are more popular than normal pressure tanks because they tend to be more efficient and durable.

🤔 What Is A Bladder Tank?

A water bladder tank is a type of tank that stores water in a flexible bladder, diaphragm, or bag, which is made from a sturdy material like rubber or plastic. The bladder is usually located in a larger tank made of metal or plastic.

The pressure of the water pushes against the walls of the bladder. As the water is used, the bladder collapses, and as it refills, the bladder expands.

The purpose of a bladder tank is to deliver water with a regulated pressure to your home’s plumbing system. With a bladder tank, you’ll enjoy a consistent flow of water, and appliances like showers and faucets will work properly.

One of the key benefits of a water bladder tank is that it takes up less space than a traditional water tank. Since the water is stored in a flexible bladder, the tank itself can be much smaller. This makes water bladder tanks a good option for homes with limited space.

Plus, water bladder tanks are relatively easy to install and maintain, making them a popular choice for many folks.

bladder tank
Cjp24, CC BY-SA 3.0, via Wikimedia Commons

🧐 What Is A Pressure Tank?

A water pressure tank is a type of tank that stores water under pressure. This type of tank is typically made of metal or fiberglass and is commonly used in conjunction with a well pump.

When the well pump turns on, it pushes water into the pressure tank. The pump stops pumping water once a certain pressure is achieved.

Then, when you switch on a faucet or a water-using appliance, compressed air pushes pressurized water out of the tank, and the pressure in the tank decreases. When the pressure drops to a certain level, the well pump turns on again to refill the tank.

Pressure water tanks have the same purpose as bladder tanks: to deliver water with a regulated pressure to your home’s plumbing system. You’ll enjoy the same benefits with a regular pressure tank as you would with a bladder pressure tank – the only difference is the tank’s design.

Air-over-water pressure tank in basement

🆚 Pressure Tanks Vs Bladder Tanks: What Are The Main Differences?

Now we know the definition of pressure tasks and water bladder tanks, how do they compare? We’ve listed the main differences below.

The Balloon System

The main difference between a diaphragm pressure tank and a traditional pressure tank system is that bladder water tanks have a balloon system, while pressure tanks do not.

This difference in design affects other features of the tanks, including their size and maintenance requirements.

System Size

The variation in size of bladder tanks and pressure tanks is the second key difference.

Bladder tanks only need to create pressurized air with the bladder, not the entire tank, which means they can be considerably smaller than standard stainless steel pressure water tanks.

The tank size affects the drawdown. Bladder tanks have a stronger and more efficient drawdown than stainless steel pressure tanks, even though pressure water tanks have so much room on the inside.

Because a diaphragm pressure tank is compact by nature, it’s able to serve multiple purposes, and is much more suitable than a standard pressure tank for smaller homes with less space.

Related: How to size a pressure tank

bladder tank vs pressure tank diagram

Maintenance Requirements

Another difference between a pressure tank and a diaphragm pressure tank is maintenance.

A pressure tank typically requires more maintenance than a bladder tank due to the increased likelihood of waterlogging. Because air and water come together inside this type of water storage tank, the air is able to gradually leak out through the water.

To prevent issues associated with waterlogging, a pressure tank needs to be inspected and reset every 3-6 months. This issue isn’t experienced with a bladder pressure tank because air and water never come into contact with each other, so inspections for waterlogging aren’t needed.


A bladder expansion tank is more efficient than a standard steel pressure tank because of the vacuum created by the balloon in the tank. In terms of air pressure, the bladder pressure tank continues to thrive regardless of the water pressure.

To create pressure inside the tank, a galvanized pressure tank requires a high volume of water, and the pressure tank loses air pressure as the tank’s water pressure decreases, which is an overall less efficient process.

Related: Expansion tanks vs pressure tanks explained


The final key difference between pressure tanks and bladder water tanks is their durability.

A standard stainless steel pressure tank is resistant to, but not immune to, corrosion. Over time, the tank’s materials will rust, affecting water quality.

You don’t get this problem with a diaphragm tank. Even if the tank’s materials corrode, bits of rust and metal won’t get into the water because the rubber lining acts as a barrier between the two.

Because of that, you can continue to use a bladder pressure tank for longer, even when it begins to corrode, without affecting your water quality.

Plus, corrosion in a bladder tank is slower because the water doesn’t ever touch the metal.

⚖️ Which Is Best: A Bladder Tank Or A Standard Pressure Tank?

So, which tank is the best option for you: a diaphragm tank or a standard pressure tank?

The modern bladder-based pressure tank is the favored choice because it’s more efficient and durable than a standard steel pressure tank, and it requires less maintenance and can be installed in locations with limited space.

Most folks will find diaphragm tanks a better value for money, but it’s still worth shopping around if you’re on the market for a pressure tank. Speak to a local plumber or well expert if you want a second opinion from a professional.

Constant pressure system beside pressure tanks

❔ Bladder Tank Vs Pressure Tank: FAQ

Do all pressure water tanks have a bladder?

No. There are several types of pressure tanks, and not all of them have a bladder setup. The oldest pressure tank type – the standard stainless steel tank – doesn’t have a bladder. The more modern bladder pressure tank does have a bladder: a rubber lining inside that separates the water and the air.

Can I replace bladder on pressure tank?

Yes, you can replace the bladder in a pressure tank. The average lifespan of the bladder in a pressure tank is 5-7 years. You’ll need to replace the bladder to keep the tank in good working order.

What is the purpose of a bladder tank?

A bladder tank is a type of tank that’s used to store and deliver water under pressure. It features a flexible bladder made of rubber or plastic encased in a rigid container. The bladder is filled with water, and the space between the bladder and the container is filled with air. The purpose of a bladder water tank is to store water in a compact and efficient manner, while also providing a way to easily pump or release the water when needed.

What is the difference between a bladder tank and a diaphragm tank?

Both bladder tanks and diaphragm pressure tanks use a flexible membrane to contain the water, but they differ in the way that the membrane is supported and how the tanks are constructed. A bladder tank contains a vinyl tank that can easily be replaced, while a diaphragm tank contains a rubber flat diaphragm, a vinyl tank, or a butyl tank that can’t be replaced.

  • Jennifer Byrd
    Water Treatment Specialist

    For 20+ years, Jennifer has championed clean water. From navigating operations to leading sales, she's tackled diverse industry challenges. Now, at Redbird Water, she crafts personalized solutions for homes, businesses, and factories. A past Chamber President and industry advocate, Jennifer leverages her expertise in cutting-edge filtration and custom design to transform water concerns into crystal-clear solutions.

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