I read the instructions on pool closing about lowering the water level to 6" below the lowest opening. I have heard conflicting advice on this step for years.
If I drain it that low, that means I will need to put in that much more water next spring. And my well provides hard water, so I would have to go through those exercises to remove the hardness.
I have a skimmer plate that keeps the water separated from the skimmer, and also the plug for the eye.
I have never lowered it that much except to replace the skimmer one summer.
Can you explain the rationale for this step?