Following pool calc precisely with wild chem swing results

smhill

0
May 11, 2013
77
Arkansas
I have measured my pool twice and used the pool calculator to determine the gallons. I have come up with 21,400 gallons. I follow the instructions on the pool calculator to a T, but I keep having wild swings in my chemistry after putting in the prescribed amounts. For example, yesterday I needed to lower my pH from 7.8 to 7.2. With a TA of 210, the pool calculator said to add 105 oz of muriatic acid-which I did. Then I ended up with a pH at 6.8 (or possibly lower because 6.8 is the lowest reading I have). Then I had to add borax to raise the pH back to 7.2 so I could do my AA treatment.

This sort of thing has happened repeatedly, and I am blowing through products like crazy. What am I doing wrong???

Thanks for taking a look-Stephani
 
Re: Following pool calc precisely with wild chem swing resul

You're overdosing. Which means you're doing the test wrong or the pool isn't as big as you think. Since the problem is consistent, it's most likely the volume.

Try using 20,000 as the volume. Pay attention to pH changes and TA changes and see if the results match. If you still overdose, try 19000. At some point you will be underdosing, and you start adding back a few hundred at a time. Keeping a log and using "effects of adding chemicals" on Pool Calculator should have you dialed in within two or three weeks.
 
Re: Following pool calc precisely with wild chem swing resul

That sounds like a good plan. I thought the depth might have been off, but I measured it again last night. It is 7' deep.

I'll back off and see what happens. Thank you!
 
Re: Following pool calc precisely with wild chem swing resul

Another hint: Measure from the bottom of the pool to the middle of the skimmer where you normally keep your water level. NOT to the top of the tile or whatever.
A 2" difference from the top of my skimmer to the middle is almost 700 gallons in my pool.
 
Re: Following pool calc precisely with wild chem swing resul

Don't forget to calculate the depth as an average depth. If you are using 7' deep for the depth you are probably off by quite a bit. If your shallow end is 3.5' deep and the deep end is 7', use 5' for your depth of pool.
 
Thread Status
Hello , This thread has been inactive for over 60 days. New postings here are unlikely to be seen or responded to by other members. For better visibility, consider Starting A New Thread.