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How to Pick Tubing Size

How to Pick Tubing Size

When planning a water garden or upgrading an existing feature, it is important to consider what tubing will be used to move your water from Point A to Point B. Tubing is rated with a maximum gallons per hour (GPH) flow rate for easy comparison with your pump's capacity. Using undersized tubing puts extra back pressure on the pump, which can cause it to fail prematurely. You also will have a reduced flow through your water feature, and you may get some leaks in your plumbing – especially if your tubing is older or in poorer condition. A good analogy would be to think about the time it would take to drink a glass of water through a standard vs. cocktail straw.

To help get the maximum flow rate from your pump, we have developed a chart to help you select the tubing size you need:

  • Up to 150 GPH: 3/8 inch tubing
  • Up to 500 GPH: 1/2 inch tubing
  • Up to 900 GPH: 3/4 inch tubing
  • Up to 1,500 GPH: 1 inch tubing
  • Up to 2,700 GPH: 1-1/4 inch tubing
  • Up to 3,600 GPH: 1-1/2 inch tubing
  • Up to 5,400 GPH: 2 inch tubing
  • Up to 13,500 GPH: 3 inch tubing
  • Up to 21,000 GPH: 4 inch tubing
  • Up to 42,000 GPH: 6 inch tubing

Tubing is available in three different types: PVC, Kink Free, and Black Vinyl. All are flexible, which will help you to avoid using 90 degree turns which can cause friction and slow down your water flow.

  • Flexible PVC Tubing - Ideal for water features with larger pumps as it available in 1-1/2" to 4" sizes. This type of tubing is quite durable, can have water in it year-round without damage from freezing temperatures, and can be buried. To join lengths of pipe or plumb your pump, you will need to use Schedule 40 PVC Slip Fittings, such as the PVC Slip Coupler, and PVC Cleaner & Cement.
  • Flexible Kink Free Tubing - The most popular and wildly used type of tubing, pairing nicely with most pumps used for water gardens. Flexible Kink Free Tubing is available in 3/4" to 1-1/2" and has similar sturdiness as Flexible PVC. Tubing is connected using barbed or insert fittings, such as the Insert Coupler, and is attached the fittings using Stainless Hose Clamps.
  • Flexible Black Vinyl Tubing - Perfect for fountains or statuaries with smaller pumps. Available in 3/8" to 1" diameter, this tubing style is also joined using insert fittings hose clamps. This type of tubing is not as robust as the as the other options and should not be buried or left out in freezing temperatures.