Apple Pool Math - latest version (Version 200) is unusable!!!

[Teaboy]

I hope I'm posting in the correct place - perhaps someone better versed in the etiquette of this forum can direct me if necessary.

Version 200 (2107) 14April 2018 of Pool Math has a serious flaw!

The ability of previous Pool Math app versions to allow the user to select the unit of mass (eg ounces, pounds, grams) has gone from the latest version - ounces is the default and no selection is offered.

Although inconvenient this is not major - I can convert ounces to grams. (In Europe, ounces have long ago been consigned to the dustbin of history, and grams and kilograms are the default unit of mass here.) My electronic balance doesn't have an pounds and ounces option.

More seriously, the amount of chemical that the app calculates is wrong - it wants me to use approximately 4 times more than I know from experience is the approximate amount I should be adding to the water.

I notice that the option to enter the pool volume still offers the choice of gallons, imperial gallons and liters (sic).

I routinely use litres, but wonder if the algorithm that calculates the required mass of chemical assumes that the pool volume is in gallons - even if the user has selected litres, given that a gallon is about 4 litres.

***edit*** Yes, if I enter my hot-tub volume in gallons (1173 litres = 258 imperial gallons) the app calculates the expected mass of chemical to be added, albeit in ounces.

I also think the look and feel of the app is not as good as the previous version, but this is a personal opinion.

Until the app is fixed, it is useless to me.

 

[Leebo]

First and foremost, WELCOME TO TFP! I see you’ve been a member for some time but few posts. I hope you’re enjoying your time here.

We have launched an update to the App that should restore the expected behavior. We ask that once you receive the update you please update us on if it addressed your issue or not.

 

[Arizonarob]

Oh, I like the weather tracking add. Nice touch!!

 

[Teaboy]

Re: Apple Pool Math - latest version (Version 200) bug work arounds

For those users who use the Apple Pool Math App to log the water quality of their hot-tub, and calculate the quantities of chemical to add, here's my current work around.

1. Note the volume of your hot tub in US gallons. (Mine is 1173 litres, so it's 309.8738 US gallons) [1 litre = 0.246172 U.S. gallons]

2. Multiply the volume of your hot tub (in U.S. gallons) by 100 and enter this value into the app as your pool volume.

3. Now measure your water quality as you normally would and enter the results into the app.

4. Use the app to determine the mass of each chemical to add. For example with a measured chlorine concentration of 0.9ppm and 34ppm cyanuric acid, Pool Math suggests adding 31oz of dichlor.

5. This is, of course 100 times too much, because you've told Pool Math that your hot tub is 100 times bigger than it is!

6. So you should add 0.31oz of dichlor.

So why step2? Why tell Pool Math that your hot tub is 100 times bigger than it is? Well, if I'd entered it's true volume, Pool Math would have told me to add 0.3oz. At first sight that looks ok, but the problem is that the app only presents the mass to a resolution of 1 decimal place... 0.2oz....0.3oz...0.4oz etc - a bit like measuring people's height to the nearest foot!
The app itself can calculate to higher resolution, but it only displays its result to the nearest 0.1oz. While this is fine if you have a swimming pool and are adding pounds of chemical, with a hot tub, 0.1oz of sanitizer can affect the concentration by more than 1ppm. You really need to know the mass of chemical to a resolution of 0.01oz. By telling the app that your hot top is 100 times bigger than it is, it delivers masses that are 100 times greater than you really need - but when you divide by 100 you get the true mass of chemical to add, with a resolution of 2 decimal places i.e. 0.31oz rather than 0.3oz.

Of course, the previous incarnation of Pool Math delivered masses in grams, to 2 decimal places with my hot tub volume entered in litres, with no multiplication by 100. The app worked beautifully!

 

[Leebo]

Have you installed the most recent update pushed out to users today?

 

[Teaboy]

Thank you for the ultra fast repair to the app - NEVER have I had this service before! Top notch.
Might you be able to restore the resolution of the mass calculation to 0.1g for hot-tub users, for whom increments of 1g in a total range of 5g represents 20% steps? Using a Scuba water tester and an electronic microbalance from eBay allows me to make very precise adjustments to water balance.

Thanks again for your quick work.