It is Total Hardness.

I have to admit to allowing a Pool Store to test my water (i'm ashamed). I was going in to buy a new floaty chair and decided to take in a sample to calibrate my Salt Test . They use the test strips/computer system.

Other than adding a little Baking Soda for the TA the water is balanced. The hardness jumped out at me.

It was a new fill last summer and our city water is naturally hard. I guess I'll live with it.