I have a small (5000 gal) concrete in-gound pool with a spa. The chlorine generator works well to keep free chlorine at a good level. My Ph, however, is ALWAYS high. If I add 24 oz of dry acid, the Ph level will be good the next day. Then the following day it will be above 8. I've been told a chlorine generator produces chlorine at a high Ph. What is going on? Should I just live with a high Ph? Should I add dry acid every other day or so to try to keep the Ph at a desirable level?
Ph issue in Salt Water pool
- Thread starter MikeRyan3d
- Start date
- May 3, 2007
- 18,052
- Pool Size
- 20000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Hayward Aqua Rite (T-15)
Welcome to the forum!
Yes SWGs increase PH. It is both part of the chemistry and the fact that they produce bubbles which aerates the water helping to raise the ph. This can be especially bad if you have high PH/TA fill water.
What is your current TA?
You can try lowering TA and see if that helps.
www.troublefreepool.com
www.troublefreepool.com
Yes SWGs increase PH. It is both part of the chemistry and the fact that they produce bubbles which aerates the water helping to raise the ph. This can be especially bad if you have high PH/TA fill water.
What is your current TA?
You can try lowering TA and see if that helps.
Lower Total Alkalinity
A lower Total Alkalinity level can help a pool owner stabalize their pH increase. We'll explain how to lower TA with a little help from muriatic acid.
www.troublefreepool.com
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We'd like to give you a few basic pointers of items that will help us, help you. From filling out a signature to posting test results.
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My TA has been running around 80, and I have periodically added baking soda to try to get it to 100. Are you suggesting keeping TA in the 70 to 90 range?
- May 3, 2007
- 18,052
- Pool Size
- 20000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Hayward Aqua Rite (T-15)
You know that baking soda raises PH too. That is likely causing your PH rise. Stop using it. Also, lower TA is better for limiting PH rise.
- May 3, 2007
- 18,052
- Pool Size
- 20000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Hayward Aqua Rite (T-15)
What is the CH level?
With a SWG and a plaster pool, same as me, I find targeting CSI to be a much better strategy. You will want to keep CSI around -0.3. Lower CSI and you could etch the plaster, higher CSI values, you may have SWG scaling issues but there is some wiggle room. You can use pool math for a PH target for the first acid dose and then go from there. If you keep the CSI target at -0.3, TA and PH will take care of themselves.
Also, you might want to switch to muriatic acid as it is much more economical than dry acid, especially with an SWG.
With a SWG and a plaster pool, same as me, I find targeting CSI to be a much better strategy. You will want to keep CSI around -0.3. Lower CSI and you could etch the plaster, higher CSI values, you may have SWG scaling issues but there is some wiggle room. You can use pool math for a PH target for the first acid dose and then go from there. If you keep the CSI target at -0.3, TA and PH will take care of themselves.
Also, you might want to switch to muriatic acid as it is much more economical than dry acid, especially with an SWG.
CH is currently at 260. It has run in the mid 300s and up to 400 in the past.
I've been getting 50 lbs of dry acid for about $85. What do you see for muriatic acid costs? I thought this dry acid cost was competitive.
I'll start looking at CSI - haven't done this yet.
I've been getting 50 lbs of dry acid for about $85. What do you see for muriatic acid costs? I thought this dry acid cost was competitive.
I'll start looking at CSI - haven't done this yet.
Started playing with the CSI tool. My issues continue to revolve around pH. With a Taylor test kit, and the color range on the tube maxing out at 8.0, I would judge my pH typically to run around 9.0 (a guess using the deep red color). pH above 8.0 shoots the CSI way up. The only way I've found to keep pH at a manageable level is to add acid every other or every third day.
- Jul 21, 2013
- 64,776
- Pool Size
- 35000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Pentair Intellichlor IC-60
Let your TA get down to 60. Even TA 50 is ok.
When your pH gets to 8 lower it to 7.4-7.6.
Just follow that routine.
When your pH gets to 8 lower it to 7.4-7.6.
Just follow that routine.
Last edited by a moderator:
jark87
Silver Supporter
- Jun 5, 2011
- 1,308
- Pool Size
- 25500
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Jandy Aquapure 1400
I’ve had the same kind of pH rise issue that you describe, but mine doesn’t rise quick as quickly as yours. I did what awj22 recommended above and that helped. pH still rises, but not as quickly.