Pool Water Circulation

Flow Data, Factors & Patterns

How are private pools set up?

The pattern of water flow in a swimming pool can be set up in many ways. Normally in a small pool the skimmers are at one end and the return jets at the other end of the pool.

It is often more convenient to put two return jets on each side of the Roman steps with a third returnjet in the middle of the top step. This helps retain the liner on the steps and also helps keep the steps cleaner.

In a large pool circulation is often set up across the pool with the skimmers down one side and the return jets down the other side.

Skimmers:

Generally, the system should be set up so that 70% of the pool flow rate goes through the skimmers.

Skimmer outlet pipe diameter	50mm	63mm
Maximum pool surface area	32 m2	36 m2
Flow rates	6 - 8 m3 per hour	8 - 10 m3 per hour

Main drains:

Generally the system should be set up so that 30% of the pool flow rate goes through the main drain(s).

Main Drain outlet pipe diameter	50mm	63mm
Maximum water velocity	0.6 m / second	0.6 m / second
Flow rates	7 - 8 m3 per hour	15 m3 per hour

Pool Return Jets:

These are generally fed by 50mm pipes and provide between 3 and 6 m3/h depending on how the flow jet is set up. Normally at least 2 return jets will be provided for every skimmer that is provided.