Well Pressure Tanks – What Size Do You Need?

Well Pressure Tank in CT

Most residential pressure tanks come in 5 sizes. Roughly, 20, 30, 50, 60 and 80 gallons.

What most people don’t realize is that pressure tanks don’t hold that much water. A general guideline is that 1/3 of the tank holds water and the rest is air. Why air?

Air is compressed inside the tank and creates pressure. The air inside your tank helps to push the water up and into your sinks and showers. A properly functioning storage tank must have air. Or – it won’t work.

To determine the proper tank size– follow this simple guideline.

  1. Get two 5-gallon buckets.
  2. Run water full blast into the bucket/s for exactly one minute with a garden hose. Just be sure no other water is running.
  3. Count the gallons.
  4. Take that number and multiply it by 4.
  5. Then round up.

For example, you ran water into your buckets for 1 minute and counted 6 gallons of water. Multiply 6 by 4 to get 24. Round up to 30. You need a 30- gallon storage tank.

The storage tank is sized to your pump’s capacity. It’s a bit more technical than that but this is a great tip for homeowners.

MOST Connecticut homes require at least a 3o or 50 gallon well tank. The 20 gallons are almost always too small and tend to be “contractor specials”. You are ALWAYS better having a larger tank than a smaller one.

This chart shows how many gallons of water is really inside your storage tank.

Pressure tank size

This assumes a pressure setting of 40/60. You can see that a 20- gallon tank only holds 5.4 gallons of water.

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