pH--soda ash vs baking soda

[CarlD]

Strictly speaking both borax and soda ash can raise T/A too. But soda ash will raise it more. Normally, as pH goes up and down it changes the T/A as well. But, by adding soda ash, for any give pH, the T/A will be higher.

If you want to raise your pH without raising your T/A, you have a 3rd option: Since your pH is 7.2, if you aerate your water your pH will rise cost-free without adding anything and without raising your T/A. You can aerate by leaving it uncovered, by pointing your return eyeballs near or at the surface, adding a small fountain, or just leaving it uncovered with the pump running. A crowd of kids works too, but only if you are convinced your water is clean of contaminants.

[cygnusecks]

My PB also said that, if you have a spa spillover, you can crank up the spa returns so that you get a lot of spillover, which will aerate the water better than the "dribble-over".

[waterbear]

airating is not without a price. It will slightly lower the TA while it raises the pH....which technique you use (borax, soda ash, airating) really depends on how much impact you want it to have on the TA
Soda ash raises both pH and TA fast
Baking soda raises ph slightly and rasies TA fast
Borax raises pH while only slightly raising TA
Airating raises pH while lowering TA, how much it lowers the TA is dependant on what the pH is when you start airating. the lower the pH the more you will lower your TA to get to the same target pH

Hope this isn't too confusing!