Aeration And Ph.

[JaredC17]

I have a few questions regarding the PH Level and using aeration. Today I got the Total Alkalinity down from 361 to 125 and the PH level between 7.3-7.5. When I use the Hot Tub I like to keep the aeration valves all the way on. Is there anyway to use aeration without raising the PH Level or is the PH Level always gonna rise to high? I am new to balancing the water chemistry for a hot tub so I am still learning about this.

Also another question I have is when adding more water to the fill line to get the water above the jets. How much will this throw the water balance off?

Water Analysis before I adjusted them. My water is well water.

TA 361

PH >8.8

CH 31

SI 1.2

I am gonna work with the Total Hardness tomorrow.

UPDATE: I got my CH to about 100 and I also super shocked the spa with Bromine Concentrate. I have been having problem keeping the bromine up. So i put 7 Tablespoons of the concentrate in and let it circulate with the cover off. The Total Alkalinity dropped even more over night to around 100.

[arches2]

The experts will be along shortly i'm sure but something to research for you would be adding 50 ppm of borates to the tub. they will lock your pH and keep it really stable. I use borax (20 mule team, right from the laundry isle), but you can also use "gentle spa" or boric acid (roach powder). With this method you'd keep you TA between 50 and 80 (whatever works in your tub to lock the pH at 7.6 or so). there are lots of thread on this board on the details.

[chem geek]

Aeration will outgas carbon dioxide if the TA of the water is above the equilibrium level for carbon dioxide in air, but in practice if you get your TA down to around 50 ppm then the amount outgassed is fairly low so the pH becomes more stable. The 50 ppm Borates provides additional pH buffering without causing any carbon dioxide outgassing. So as the previous post stated, get your TA down into the 50-80 ppm range and use 50 ppm Borates. That combo should keep the pH in check when using net pH neutral chemicals such as bleach (accounting for the acidity of chlorine usage/consumption).