Ta Problems

[pooltrouble]

I have a 40500 gallon vinyl pool with an alkalinity reading of 230 at the opening of the pool. I use liquid chlorine as a sanitizer. I have been adding muratic acid to reduce the alkalinity - 6 gallons over a two week period. The alkalinity is now reading 150. The PH is never lower than 7 ppm.

I read on the forum about agitating the water. Is it to late to start that process now that I have added all the muratic acid? Is the water safe to swimming in with that amount of acid in the water?

[waterbear]

I have a 40500 gallon vinyl pool with an alkalinity reading of 230 at the opening of the pool. I use liquid chlorine as a sanitizer. I have been adding muratic acid to reduce the alkalinity - 6 gallons over a two week period. The alkalinity is now reading 150. The PH is never lower than 7 ppm.

I read on the forum about agitating the water. Is it to late to start that process now that I have added all the muratic acid?

No, not at all, The agitation speeds up the out-gassing of carbon dioxide so it speeds up the process. The act of adding acid lower the TA. The acid combines the the bicarbonate ions in the water (your primary source of TA) to form water and carbon dioxide. Carbon dioxide dissolved in water is carbonic acid (think seltzer water or club soda,basically the same thing) As the CO2 gasses off the amount of carbonic ACID decreases and the pH rises again

Is the water safe to swimming in with that amount of acid in the water?

If the pH is 7.0 or above it is safe to swim. pH below 7.0 is not safe for vinyl liners, btw.

Realize that the amount of acid added is neutralized by the bicarbonate that exists in your water.

I would suggest reading this and if you don't already have one, invest in a Taylor K-2006 test kit, which has the acid demand test you need to make this job easy with no guesswork. It will be the best investment you can make into your pool care and save you a lot of money in the long run. You want to lower your TA enough so your pH becomes stable and does not rise too quickly. In a vinyl pool using liquid chlorine a TA of around 70 is a good starting point, FC should be 3-5 ppm and CYA about 50 ppm (unless your climate conditions demand otherwise). pH should stabilize around 7.6 or 7.7 You want to keep the pH below 8.0 and the additon of 50 ppm borate can be helpful.