Skimmer hole question

[KentfamPool21]

Company opened pool a few days ago, after cleaning up when they left I noticed they forgot to pull plug on skimmer farthest from equipment pad to get the suction going.

The skimmer has another hole at the front (closest to pool). I asked the company if I should put the plug on the other hole closest to the pool and they said “should be fine to leave it off”.

After reading here it seems this hole is connected to the main drain at the bottom of my pool (older pool). The main drain is not ran back to the equipment pad. Only two lines running back to the equipment pad are the 2 skimmers.

Question:
Do I leave the other hole open or put the plug in that hole?

It has been out the past two days with zero issues, when I put my hand over the hole there is no suction.

Thanks

 

[AQUA~HOLICS]

The hole closest to the water is designed to continue water flow to the pump when the water level is below the skimmer mouth, water is then pulled from the main drain.
If the skimmer is provided with a diverter valve, water can be adjusted between the skimmer and the main drain.
During normal operations this hole will have no suction unless the safety valve located directly above is set to do so.
So to answer your question the skimmer was designed to have both holes open.

 

[KentfamPool21]

The hole closest to the water is designed to continue water flow to the pump when the water level is below the skimmer mouth, water is then pulled from the main drain.
If the skimmer is provided with a diverter valve, water can be adjusted between the skimmer and the main drain.
During normal operations this hole will have no suction unless the safety valve located directly above is set to do so.
So to answer your question the skimmer was designed to have both holes open.

Thank you!! In what situation would I ever plug that front hole?

 

[AQUA~HOLICS]

That I don’t know, we are in two different states that have different ways of running pools for winter. In my area of SOCAL no closing down for freezing temperatures are followed so pools can be used year round.