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blentz
06-13-2012, 08:04 PM
Hi,

I have a concrete indoor pool with a coverstar electric cover. I have been battling with pool water chem for several months now. My PH is bright pink 8.0 or higher on my taylor test kit. Total Alk is 100ppm. The water is clear and there is no scaling or calcium build up on the pool or equipment. Should i try and get lower PH or just go with it?

I found Ben's article on how to get correct PH/ALK by aeration and have employed this technique while keeping the cover open.

However, i don't understand how i can have high PH and correct Total ALK.

Thoughts on how to get lower PH and correct Alk?

Thanks in advance,

Bob Lentz

Watermom
06-14-2012, 12:17 AM
You'll have to use some muriatic acid to lower the pH and then use some baking soda to raise the alk back up. Please read the using muriatic acid safely link in my signature below.

Welcome to the Pool Forum!

waterbear
06-14-2012, 01:34 AM
Hi,

I have a concrete indoor pool with a coverstar electric cover. I have been battling with pool water chem for several months now. My PH is bright pink 8.0 or higher on my taylor test kit. Total Alk is 100ppm. The water is clear and there is no scaling or calcium build up on the pool or equipment. Should i try and get lower PH or just go with it?

I found Ben's article on how to get correct PH/ALK by aeration and have employed this technique while keeping the cover open.

However, i don't understand how i can have high PH and correct Total ALK.
IF your pH is climbing too high then your TA is too high. Period.
Thoughts on how to get lower PH and correct Alk?

Thanks in advance,

Bob Lentz

TA (or ALK is a measure of how much bicarbonate is in the water. It is the amount of carbonation in your pool (much like a bottle of club soda) The bicarbonate exists in conjunction with carbonic acid (and this is our buffer system). However carbonic acid is basically CO2 dissolved in the water and when the CO2 gasses off into the air the pH rises (because the amount of carbonic ACID has decreased (operative word here is acid).
If we lower the amount of bicarbonate in the water (lower the TA) then there will also be less carbonic acid (remember, this is a buffer system and there is an equilibrium between the amount of carbonic acid/bicarbonate ion in the water)
If there is less carbonic acid it means there is less CO2 in the water to gas off and that means the pH won't rise as fast
SO if you pH is always rising too high too quickly then lower your TA. It's that simple!
Since your pool is plaster you might need to raise your calcium hardness to keep the water balanced if you make big changes to the TA.
YOu did not asay what your calcium hardness is and that is important to take into consideration, along with pH and TA in a plaster pool to make sure the water is neither scaling nor aggresive and damaging to the plaster.