Borax & MA Computation Differentials

[bxcrwlly]

Looking for clarification. I used "waterbear's" 2008 posted calculations to determine the quantity of Borax and MA needed to adjust my pool to the desired borate level. Just for grins, I hopped over to the pool calculator and ran a comparative. I noticed a 27-29% higher differential with waterbear's data vs. the pool calculator. I also used a couple of other software apps that agreed with the pool calculator.

While not a huge issue, just curious why there would be any differential. Thoughts?

 

[Patrick_B]

Sorry I don't know, but I am sure Jason or Richard have the answer. Honestly, I would trust PoolCalculator.

 

[duraleigh]

Use the poolcalculator.

 

[JasonLion]

I get a difference of less than 5% on the borax acid ratio. waterbear says 2 to 1 borax to acid, and Pool Calculator is about 2.098 to 1 (before rounding). An error of 5% isn't going to make all that much difference. There is also an error of just a tiny bit less than 2% in the quantity of borax to use in waterbear's directions. Rounding can increase those errors, especially for small quantities, but with small quantities it really doesn't matter much.

The Pool Calculator tries very hard to be exactly right, while waterbear was trying to give you something that would be easy to calculate in your head.

 

[bxcrwlly]

All...appreciate the clarification. As info, I was comparing borax to borax computations vs. borax to acid ratio. Here's my comparisons.
waterbear: 15,600 gallon pool raising borate by 10ppm. 12X15.6=187 ounces or 2.5 boxes
pool calculator: 15,600 gallon pool, borates now 30 raising to 40. Requires 137 ounces or 1.8 boxes
I divided 137 by 187 (=(137/187)-1) = .27 rounded up

Not a big deal, just wanted to explain my numbers. As always I do appreciate the quick responses and assistance from the forum. Long live TFP!