How do I calculate the capacity of my pool filter?

Author: Jolie Marvin IV  |  Last update: Friday, May 8, 2026

Example: Say you want to set up the pool to have an 8-hour turnover rate. The equation to find the flow rate for a 29,920-gallon pool (regardless of its shape) is: 29,920 ÷ 8 = 3,740 gph. To calculate the flow rate per minute in this case: 3,740 ÷ 60 = 62.3. That's the rate at which you'd want the filter to work.

How do you calculate filtration capacity?

How to Calculate Filtration Rate
  1. Circulation Rate: 100 cubic metres per hour.
  2. Filter Surface Area: 5.71 metres squared.
  3. Filtration Rate: 125m3 / 5.71m2 = 21.89m3/m2/hr.
  4. Width of filter: 2.7 metres (this is also the diameter)
  5. Radius: 2.7m / 2 = 1.35m.
  6. Radius Squared: 1.35m x 1.35m = 1.82 m2.

How do I calculate the capacity of my pool pump?

Select the Right Size Swimming Pool Pump
  1. Circular Pools: Diameter (ft.) x Diameter (ft.) x Average Depth (ft.) x 5.9 = Total pool capacity in gallons.
  2. Oval Pools: Length (ft.) x Width (ft.) x Average Depth (ft.) x 6.7 = Total pool capacity in gallons.
  3. Rectangular Pools: Length (ft.) x Width (ft.) x Average Depth (ft.)

What is the formula for the capacity of a pool?

Length x width x depth x 7.5 = volume (in gallons)

Multiplying that by the depth gives the volume in cubic feet. Since there are 7.5 gallons in each cubic foot, multiply the cubic feet of the pool by 7.5 to arrive at the volume of the pool, expressed in gallons.

What size filter for a 12000 gallon pool?

When choosing a pool filter for your above ground pool, there's a helpful rule of thumb to keep in mind: Sand filters: at least 1 square foot of filter area per 10,000 gallons of pool water. Cartridge filters: at least 100 square feet of filtration area per 10,000 gallons of pool water.

How to Correctly Size a Sand Filter

How to calculate filter size for pool?

Before putting it all together make sure you've correctly calculated the pool's volume (in gallons) and decided on a reasonable turnover rate for all the water to be cycled through the filter. The equation used in calculating filter sizes is: Pool capacity in gallons divided by the desired turnover rate in hours.

Is it OK to oversize pool filter?

Selecting a small one for a large pool will require frequent filter replacements and might even break down under pressure, while the one that is too big will work too quickly and powerfully, and might make the pool unsafe. Therefore, it is essential to size the filter properly.

How do I calculate how many gallons my pool is?

Length times width gives the surface area of the pool. Multiplying that by the average depth gives the volume in cubic meters. If you'd like to find the pool volume in gallons, multiply your results by 7.5, as there are 7.5 gallons for each cubic foot.

How to calculate the volume?

Height × width × depth = volume

If the height, width and depth are measured in cm, the answer will be cm³.

How we can calculate pump capacity?

The shaft power of the pump = water supply (liter/sec) × head (m) / 102 × efficiency = flow × head × density × gravity acceleration.

What size pool pump do I need for a 25,000 gallon pool?

In that case, we would look for a pump in the 50 – 60 GPM range. If you have a pool/spa combination, you need to consider the flow requirements of the spa jets. This will often push you towards a pump on the higher end of the acceptable scale. In that case, we would look for a pump in the 75 GPM range.

How many gallons is a 16x32 pool?

16 feet x 32 feet =512 square feet. If you mean 52 inches for the depth, that would then be 4 1/2 feet. Then 512 sq ft times 4.5 feet woud be 2304 cubic feet. then 2304 cubic feet times 7.4 gallons per cubic foot would be 17,049.6 gallons in this pool.

How do you calculate the filtration rate of a pool?

Don't mistake it for the flow rate, which is the speed at which water travels through the entire circulation system. To calculate the filtration rate, you simply divide the flow rate by the filtration surface area.

What is the equation for filtration?

The equation for constant rate filtration is Δ P = μ α av c A 2 ( V ) d V d t + μ R m A d V d t Eq. (5) should be linear, provided that the average specific resistance and dry cake mass per unit volume of filtrate are constant; i.e. for incompressible filtration.

How do you calculate filter volume?

To determine the volume of water passing through the filter, we will use the following formulas:
  1. Area = Width x Length.
  2. Volume = Area x Height.

How to calculate how many gallons?

Formula:
  1. Formula:
  2. L x W x D. = Cubic Feet.
  3. Cubic ft x 7.47. = Gallons.

How much chlorine for a 1000 gallon pool?

It usually falls between 10-12.5%, with 12.5% being the most common value. Adding 0.13 ounces of pure chlorine to 1,000 gallons of water will raise the chlorine levels by 1 ppm. These numbers are the basis for all your calculations for adding liquid chlorine to pool water.

How do I find capacity?

Determining Capacity & Volume
  1. Rectangle or Cube Shape. Length X Width X Height. Example: Length is 72", the width is 48", and the height is 60" ...
  2. Cylinder Shape. pi X radius squared X Height. ...
  3. Cone Shape. 1/3 X pi X radius squared X Height. ...
  4. Sphere or Circle Shape. 4/3 X pi X radius cubed.

What is capacity calculator?

This is a simple tool that helps you to understand the time you have available for your main work activity, e.g. seeing patients or managing a service. It is an Excel spreadsheet that calculates this for you if you enter the time spent on various activities.

How do you calculate specific capacity?

The Specific Capacity of a well is simply the pumping rate (yield) divided by the drawdown (Figure 1). It is a very valuable number that can be used to provide the design pumping rate or maximum yield for the well.

How do I know what size filter I need for my pool?

Another rule of thumb for pool filter size is to look at the swimming pool size in gallons. If you've never calculated this before, take some measurements. The formula is Length x Width x Average Depth x 7.5, for rectangular pools. For oval pools, change 7.5 to 5.9.

What happens if your pool pump is too big for your pool?

A pool pump that is larger than needed has a more powerful motor and circulates water at a higher flow rate. This uses significantly more energy to pump the same amount of water and puts additional stress on your pipes and filter, meaning you'll need to replace them sooner.

How full should a pool filter be?

Make sure you have the proper amount of sand in your filter. Remove the dial valve and inspect the level of sand, the sand should be 1”-2” below the bottom of the basket. Also make sure the upper standpipe and lower standpipe are connected tightly into the basket.

Previous article
What are the disadvantages of pods?
Next article
Can mice warn other mice about traps?