Converting to salt with a very high CH

[thilbert]

Yep, numbers are correct. Yep, the pH was much higher when I started cleaning up, as was TA. I've been keeping the pH fairly low along with daily brushing, and while it seems to help, you really need to get in the pool and scrub with a light 3M pad - the blue one - to get the stuff to come off completely.

On a related side note, I went through a 1.5 gallons of 31% MA and had to buy more. The MA I had was a couple of years old. I had to buy new stuff and I noticed that it had a much more dramatic effect than the old. I looked over my log and realized that the pH was not changing as it should with the addition of the old MA (the pH change wasn't even close to the pool calc). I guess MA can go bad?!

Here's to hoping that using new MA will improve scaling matters.

Need a line on that calcium specific sequestrant if you have a brand name, please. I'd rather not get it from the pool store that shall not be named.

Oh, not to put too fine a point on it (and not that it changes the SI too dramatically) but here in DFW, my water temp is hovering around 88. Kids and wife love it, but I have to say I prefer a cooler pool, especially in August when it's 105 until the sun goes down.

Are you sure your numbers are accurate? If I calculate the saturation index using those numbers and a water temperature of 80ºF (and using 7.15 for pH) I get -0.27 which should not be scaling. Was the pH much higher when you opened the pool (or the other numbers)? If so, then that might explain the scaling.

The scale can be redissolved by having the pH kept low (but probably not below 7.0 for too long) along with some brushing and if that doesn't seem to work then there are calcium scale reducing products which are metal sequestrants that are focused on holding calcium and dissolving scale. Others on this forum might have some special tricks for dissolving scale.