How to add Borax

[chem geek]

Raised the chlorine to 8, do you think this is too high? Typically it drops 2 ppm in a day, maybe after the borax 1, but will have to wait for time to tell.
What is the optimum CSL level?
The pool is crystal clear but was thinking of raising the calcium to 400 based on your spreadsheet, your opinion would be appreciated. What would be the benefits of doing this.
Noticed in one post that you said there might be a benefit in raising borate to 100 but no other detail as far as I can see. Would it be wise or unwise to do so, or are the benefits minimal versus any downside?

You could probably target 4 ppm as your absolute minimum and therefore start with 6 ppm at the start of the day, assuming it still loses 2 ppm per day. It may lose less per day after the Borate settles down and will also lose a little less if you start out with 6 instead of 8. It's really up to you if you want to be on the lower end of Ben's range or the higher end though you will use less chlorine at the lower end. If you think you might miss a daily dose, then 8 ppm is a safer starting point.

If you are worried about the -0.2 CSI index, that is not bad at all and you can just leave things as they are, but if you wanted to you could add more calcium. I think that 300 ppm is plenty for CH since it still gives you plenty of leeway to have the pH higher or lower. It's easy to add calcium, but a pain in the patooty to get rid of it (essentially by dilution). Honestly, don't worry about a CSI variation of anything less than +/- 0.5 (and yes, I know I've got a warning orange at +/-0.3 and a danger red at +/-0.6 but that's really conservative and most people don't see any problem at all until they get to +/-0.75 or even much higher).

As for the 100 ppm Borates level quoted in the Who document as being more effective against more types of algae, I would stick with the 50 ppm for now since that's what is recommended by Proteam and others. Let's see how it goes for you, waterbear (Evan) and others before we go any higher on Borates. I'm just being conservative about this -- I don't see any real downside to the higher Borates level (see the section on Human exposure to Boric Acid in the same Who document at this link).

And yes, you can let your TA drop to 90 if you want since that will also help reduce the pH rise. You can also operate at somewhat higher pH, 7.6 (or to 7.7 if you lower your TA to 80). Again, these CSI "0" targets are very conservative targets and you have a lot of leeway before you would get into a scaling or corrosive situation. It's my personal goal to target the "0" for my pool, but I don't worry about it deviating so it's really a long-term "annual" starting point goal more than anything else.

Thanks for keeping us posted on your experience.

Richard