Questions on returns and plumbing.


Well-known member
Mar 21, 2008
Hello all, yet another question or two:

When plumbing suction, I have read somewhere that you need to plumb them in a ring so that all suctions are feeding off the same line such that there is no difference in pressure. Does this also apply to returns?

On a 12-15k gallon pool is adding a floor return at the deep end wise? Does anyone know what the costs are of this type of return vs in wall?

For safety should you insist on dual main drains? (anti-vortex in case one gets plugged)

Thanks again.
- John


Active member
Nov 6, 2007
i dunno about the ring, but the dual mains is required by code in long beach where i live...


TFP Expert
LifeTime Supporter
May 3, 2007
Pleasanton, CA
A loop can equalize flow but it also tends to reduce total flow. An easier way to ensure equal flow is to have separate pipe from each port going all the way back to the pad and put ball valves on each line before combining them. This way you can control the flow from each suction line separately and you can even turn one off if needed.

However, it really isn't that important to have equal flow from each port. If designed properly, there will be plenty of flow from everything. Having separate lines for each main drain pair and skimmer will ensure that you have plenty of flow from each. The ball valves add a little more control but normally you will want to run them wide open.

For return lines, having equal flow rates to each return is probably less important. By using a single large return line or better yet multiple large return lines, you can be assured that there will be plenty of flow for each return. As long as the length of line for each return is not significantly different than the others, the flow rates should be close enough.

Dual main drains are a good idea if you decide on heating the pool. Pulling colder water from the bottom will help to evenly distribute the heat throughout the pool. If you decide to go with a main drain, I would definitly put in duals but the city will probably make you anyway.