Controlling high pH in spa

[pgershon]

Yeah. You definitely have a remineralization post filter, probably crushed limestone. It’s adding both mineral hardness and carbonate alkalinity. You’d be better off filling the pool/spa with the untreated water as long as there aren’t metals in it like iron.

You can fill up a 5 gallon white plastic bucket with a gallon or two of untreated water and add 2 cups of bleach. Let it sit for a while and see if the water turns tea colored. If so, you have iron. Long Island well water is full of iron.

I will do the iron test, but we had our well water tested by a NY lab in 2018. Results attached.

 

[pgershon]

You can fill up a 5 gallon white plastic bucket with a gallon or two of untreated water and add 2 cups of bleach. Let it sit for a while and see if the water turns tea colored. If so, you have iron. Long Island well water is full of iron.

Water has been sitting in bucket for 3 hours now and has not changed color. I will give it until the end of the day, The report I had from NY State lab 3 years ago did not find iron either

 

[pgershon]

One more question. I am probably going to switch the pool/spa autofill to untreated well water. I see no evidence of iron, although I wonder why I initially got the filtration - I think to treat acid but what I was sold was insufficient so I needed a second purchase. Bottom line is that I have no memory of iron problems and no evidence of iron today...

However, as I looked at the autofill, the treated water is run through two filters at present. One is a 10,000 gallon metal trap (their smallest size) and the other is a Jandy 2888 Ray-Vac Energy Filter with Gauge. I also noticed that black crud has been caught in the Jandy filter (see photo). I am guessing the crud came from the metal trap as opposed to the treated water, but who knows. The Metaltrap is probably 5+ years old as I dont recall paying for a new one recently. The Jandy is new because last year's filter froze and broke when I kept the autofill on into late October (for the spa) Would you be concerned about the water based on what I have said? I think I should probably get rid of the Metal Trap as its likely spent and not replace it.

Thoughts? Thanks again in advance @JoyfulNoise .