Question on using pool math

[Testinglife]

Hello, can anyone help figure out which one to trust between my regular chem trackers and it's chemical recommendations compared to the effects of adding section? I get different suggestions.

For example if my ph was 8.5, my tracker section when I click ph might say add 25 grams of dry acid to get 7.5 ph but then when I put 25 grams of dry acid on the effects of adding section it only lowers it by .4 ppm which would only take me to 8.1. and then i manually enter numbers until I get 7.5 and it's more like 60 grams.

This is just an example of how they vary but it happens other ways too. So I am trying to figure out which one is more reliable and maybe understand the differences.

 

[PoolStored]

I would suggest that Pool Math is accurate. I don't know what other tracker you are using and how the calculations are performed.

If you are using acid to lower pH you should get the following message below the effects of adding. I would lower pH in .4 increments using pool math's recommendation. Test and adjust again.

 

[sande005]

If you mean the recommended amount as shown in the logging section of Pool Math vs the Effects of Adding section -

At 65,000 liters (your pool volume as shown in your logs here), the logging section suggests 41 oz (or 1,162 grams) to move from 8.5 to 7.5.
In the Effects of Adding section, it reports that 25 grams will have 0 effect.

Check your pool size, and the units of measure.

Note the disclaimer under "Effects of Adding" -
It is only approximately correct if pH is 7.2-7.8 and the change is +/- 0.4.
Your starting pH is much higher, and the change desired is more than double. You've exceeded the parameters of the software.
Never make such big changes all at once, for any chem level. Always better to sneak up on it with a couple of rounds of testing and additions.

If you are trying to compare to some other "chem tracker", especially without knowing what that is, we cannot express an opinion. We do know that Pool Math has been in use for many years by many hundreds of thousands, and has proven out to be very dependable.

You are further north than I am. I have to chip a piece out, bring it inside to thaw and come up to room temp. before I can test it. Might be hard to get the additions to mix well.

 

[Newdude]

+1 Testing life. Please Fill out your signature so we can see all your relevant info at a glance. Maybe it's an indoor pool and your season never ends. Maybe your outdoor pool is winterized and you shouldn't be messing with it because it needs to be well mixed before testing and after adding. Maybe it's just a theoretical question looking forward to the upcoming season.

I just did it the hard way to see that in previous posts you mentioned high debris in your yard, so it's outdoor.

Are you adjusting the pool now or just looking for insight ?

Also narrow down your location to the general area. Canada might be mild on Vancuver Island or 'you have to be kidding me cold' north of Montreal.

 

[Mdragger88]

As @sande005 mentioned the “effects of adding” tool assumes a couple of things that will make it slightly different from the overview tabs/cards calculations which actually take into account your other parameters.