Main Drain and Skimmer Percentage Split

[rich6429]

Hi - disclaimer...new pool owner here

I see a lot of articles and posts where the percentage split for the water pumping back into the filter has been in the range of 70%-80% Skimmer and 20%-30% Main Drain. My pool currently has 2 Main Drains and 1 Skimmer. I certainly can follow the recommended and suggested percentages I have seen, which leans more of a higher percentage towards the skimmer. However, I would like to understand why higher on the skimmer and not necessarily a 50/50 split between the Main Drains and Skimmer.

Thanks

 

[Berger82]

Hi - disclaimer...new pool owner here

I see a lot of articles and posts where the percentage split for the water pumping back into the filter has been in the range of 70%-80% Skimmer and 20%-30% Main Drain. My pool currently has 2 Main Drains and 1 Skimmer. I certainly can follow the recommended and suggested percentages I have seen, which leans more of a higher percentage towards the skimmer. However, I would like to understand why higher on the skimmer and not necessarily a 50/50 split between the Main Drains and Skimmer.

Thanks

I split my skimmer:main drain about 60:40. The reason for higher skimmer is to create more (stronger) suction, thus pulling more debris from the water surface.

 

[Newdude]

The main drains really don't 'pull' anything. There was a video here with dye that I couldn't find the last several times I tried to post it, but the dye only moved a couple inches on top of the drain. Like 3 inches. And it moved slowly, not with the wooooosh you would expect. Have them cracked 10% just to pull some water from the bottom as a pump failsafe and let the skimmers have 90% of the suction where it's needed.

 

[Homebrewale]

I leave my main drains closed so 100% of the water returned is from the skimmers. I do this because I leave the rpms low on my VSP and still want some skimming to occur.

 

[Jimrahbe]

Rich,

What do you think the main drain does??? What are you concerned will happen if you shut it off?

You only have one main drain, it will have two covers, but they connect to one pipe going back to the equipment pad.

I suggest running with the main drain fully closed, or opened just a small amount like 5 or 10%.

Pools don't even need main drains at all.

That said, it is your pool and you can run it however you wish. If your skimmer works well with the 50/50 split between the main drain and skimmer, then just run it that way. Whatever works best for you.

Increased skimmer flow is the main reason to reduce or shut off the flow from the main drain. This is much more noticeable with VS pumps running at a low RPM.

Thanks,

Jim R.

 

[Noreaster]

Do you have an infloor cleaning system, aka caretaker?

 

[rich6429]

Rich,

What do you think the main drain does??? What are you concerned will happen if you shut it off?

You only have one main drain, it will have two covers, but they connect to one pipe going back to the equipment pad.

I suggest running with the main drain fully closed, or opened just a small amount like 5 or 10%.

Pools don't even need main drains at all.

That said, it is your pool and you can run it however you wish. If your skimmer works well with the 50/50 split between the main drain and skimmer, then just run it that way. Whatever works best for you.

Increased skimmer flow is the main reason to reduce or shut off the flow from the main drain. This is much more noticeable with VS pumps running at a low RPM.

Thanks,

Jim R.

Thanks. I actually didn’t know the difference or function ofthe split. Thanks for clarifying. I always thought the main drain was better for circulation. That said, I have been running my vsf with lower rpm, so will take the suggestion of either closing or having minimal flow through the drain.