Swimming Pool Acid

[chem geek]

I totally agree. Even adding one pound of dry acid each week per 10,000 gallons (which is equivalent to about 1.5 cups of liquid Muriatic or Sulfuric acid) would add about 250 ppm over 6 months which only starts to affect water chemistry (it's equivalent to a drop in pH of 0.1 as far as calcium carbonate equilibrium is concerned).

Adding one pound of non-chlorine shock (potassium monopersulfate or KMPS) each week per 10,000 gallons would add about 200 ppm sulfate over 6 months.

So if someone had a regimen of adding these chemicals on a regular basis and did this over years without significant dilution or replacement of their water, then I could see a problem slowly emerge, but as waterbear points out the problem is not worth worrying about until the sulfates get really high.

Personally, I use winter rains to dilute my pool by about half each season just to keep whatever is building up under control, but that costs me in chemicals each season as I have to build back up the calcium, carbonate and CYA. If I start using salt (1000 ppm) and borates (50 ppm Boron) next year, then I'd have to add those as well. Perhaps I'll stop my annual dilution regimen!

Richard

[PatL34]

If you are using a SWCG, then IMHO, the only acid you should be using is muriatic acid. It makes things easier.
Pat