How long do chemicals stay in the pool?

[Jeff J.]

I was just wondering how long all the different chemicals we put in a pool stay there. Chlorine obviously starts disappearing almost as soon as it hits the water. And some, like salt, are said to stay there forever, except for splashout. Some, like CYA, degrade slowly. What about all the others, like baking soda, borax, muriatic acid, dry acid, polyquat, borates, etc.?

 

[mknauss]

Most of the 'others' you list react when added to the water. Baking soda, borax, acid all react and are not in their original form once added. Polyquat degrades. Borates are like salt. Splashout, over flow, etc remove them.

 

[peterl1365]

I added borates to my pool back in early 2013 or so. I tried to shoot for 35PPM using boric acid. Since then, I've done a couple of partial drains to lower CH and to repair a bunch of pool tiles that were shaken loose by an earthquake. I might have added 1 or 2 boxes of Borax following the tile repair (2-3 years ago), but I don't remember exactly how much.

Is there any chance that there are any measurable borates left in the pool? I have test strips, but they are more than 5 years old and probably no good any longer. Would I be safe in assuming that no borates remain and just shooting for 30PPM?

 

[mknauss]

I would suspect you have minimal residual borates in the pool water.

 

[peterl1365]

Thanks. I tried my test strips (which have a 4/2018 expiration date) and they seem to indicate that I have something between 0-15 ppm.
However, my color vision is notoriously bad, so I really don't have any idea.
I'll just assume that I have less than 10 ppm. I just ordered 15 lb of boric acid, so that should get me into the 25-30 range.