For the next few days I am beta testing some improvements to my Pool Calculator. You can access the beta test version at Pool Calculator.
The Pool Calculator now remembers it's configuration. Units, pool size, goals, etc are all saved between sessions.
It is now easier to work with spas and very small pools. Small numbers of oz are now shown to the nearest tenth of an oz and if you mouse over a volume it will now show teaspoons in the info bar when appropriate.
The amounts of chemicals recommended to change the PH now take the current PH and TA levels into account. The calculation is still approximate and doesn't take other factors that might affect the quantities required into account, but in general it is now far more accurate than it was before.
This is a beta test version, as such not everything may work correctly and amounts of chemicals or other calculations might be wrong. Because of that I am leaving the old version up at the normal URL for the next few days. When this version has gotten more testing I will replace the previous version with the new one at the normal URL.
I welcome any testing, feedback, questions, or comments you may have!