johnnyL's thread --- Am I close on these figures?

[johnnyL]

Hi all! I am new to the pool owner category (about 3 months) so I have been doing some research on properly maintaining a pool. In my internet research I found the BBB method. I have been using that method with great success thus far with the approach of adding a little bit at a time and retesting 24hrs later.

What I have tried to do is gather some basic figures as far as how much to add of something to change the pool chemistry by xxx ppm. So I am gonna post the results that I have thus far and I would like people to respond with a yes or no on whether any/some/none of them are correct and which specific ones are correct or incorrect. Additionally, if any are known to be incorrect, hopefully the correct values would be supplied by the responders. That would be most helpful and appreciated!

Anyways, thanks in advance, and here are my findings thus far. BTW, all these values would be for a 10,000 gallon pool as an example.

Adding Baking soda to raise alkalinity - 10,000 gals
1 lb = ~ 7 ppm increase in TA and only .01 ppm increase in pH
amt TA/\ pH/\
1 lb 7 .01
2 lb 14 .02
3 lb 21 .03

Adding 6% Bleach to raise chlorine - 10,000 gals ... ??? These don't sound right to me ... seem very high to me
amt FC/\ Salt/\
16 oz .8 1.3
32 oz 1.6 2.6
48 oz 2.4 3.9

Adding Borax to raise pH - 10,000 gals
1 lb = ~ .18 ppm increase in pH and 3.1 ppm increase in TA
amt pH/\ TA/\
1lb .18 3.1
2lb .36 6.2
3lb .54 9.3

Adding Calcium Chloride to raise Calcium Hardness - 10,000 gals
1 lb = ~ 11 ppm increase in Calcium Hardness
amt CH/\
1 lb 11
2 lb 22
3 lb 32

Adding Muriatic Acid (31.45%) to lower Alkalinity/pH - 10,000 gals
amt TA\/ pH\/
16 oz 6.5 .38
32 oz 13 .76
48 oz 19.5 1.14

Adding Stabilizer to increase CYA - 10,000 gals
1 lb = ~ 12 ppm increase in CYA but lowers the pH by .22 ppm
amt CYA/\ pH\/
1 lb 12 .22
2 lb 24 .44
3 lb 36 .67

Adding Washing Soda or Soda Ash to increase pH and Alkalinity at the same time - 10,000 gals
1 lb = ~ .35 ppm increase in pH & 11 ppm increase in TA
amt pH/\ TA/\
1 lb .35 11
2 lb .70 22
3 lb 1.05 33

Lemme know please. Once I get the correct values for the above, I plan on passing on some info that will probably be most appreciated for others here on this forum.

[PoolDoc]

Hi Johnny;

I can tell you that some of your calculations are wrong, but I'm not going to get into to trying to correcting them.

The most authoritative calculations for what you are trying to do are found in Chem_Geek's spreadsheet, here:
http://richardfalk.home.comcast.net/...lEquations.xls

However, trying to calculate pH results accurately requires very detailed knowledge of all the acids, bases and buffers in the pool, which in turn requires more accurate and comprehensive testing than can be done with most pool kits. And, as you'll see from Richard's spreadsheet, even then very elaborate calculations are needed to determine pH change.

As a practically matter, this information is usually not very helpful. Attempts to 'single-shot' your adjustment doses can cause serious problems, which is precisely why my BBB Method uses a 'test - dose - retest' approach.

Ben