Normal acid additions?

[MaxSpeed144]

I wondering if anyone can chime in with the volume of acid they add to keep the pH in the proper range for a pool with SWG?

For me I seem to be adding about 500-700 ml every 3 days or so. The pH rises to about 7.7 and then comes down to 7.4-7.5 (checked after 24 hours). Is this normal?

I have a small pool 12k gal/45k L with Pentair IntelliChlor 20 set to about 30% and the VS pump runs for 24h.

I occasionally add baking soda to bring the alkalinity back up.

Currently the other attributes are:
FC 3.5
CC 0.2
TA 80 (corrected)
CYA 50
CH 220
Salt 3300
Temperature 83

 

[PoolStored]

We don't use corrected TA. What is the actual result from your test (uncorrected) for TA?

You are fighting against the pool with the acid additions and baking soda...that will be a never ending cycle.

A pool with an TA (uncorrected) of 60-80 will have a fairly stable pH around 7.8-8.

There is no reason to force pH down to 7.4/7.5. If it is stable at 7.7-8.0, leave it alone...

Post the uncorrected TA.

 

[MaxSpeed144]

We don't use corrected TA. What is the actual result from your test (uncorrected) for TA?

You are fighting against the pool with the acid additions and baking soda...that will be a never ending cycle.

A pool with an TA (uncorrected) of 60-80 will have a fairly stable pH around 7.8-8.

There is no reason to force pH down to 7.4/7.5. If it is stable at 7.7-8.0, leave it alone...

Post the uncorrected TA.

The uncorrected is 100, but I have never tested for borates.
The baking soda has been added only every two weeks while the acid is quite frequent.
I was under the impression the the pH needed to be in the 7.4-7.6 window?

 

[PoolStored]

With a TA of 100, you should not be adding baking soda. You should target a TA of 60-80.

Ignore TA and manage your pH for the most part. Keep it between 7.6 and 8. If it rises to 8, lower to 7.6. pH will rise on its own. Doing this will lower TA over time.

When your TA gets to 80...stop lowering to 7.6. Only lower to 7.8 and your pH should be fairly stable.

 

[MaxSpeed144]

Ok thank you, I'll try that. Is the saturation index the more important attribute to keep balanced then? I have the Taylor Watergram hand calculator thingy.

 

[PoolStored]

Download pool math, will help you with all the calculations you need. Link-->PoolMath

Pool math includes a calculation of CSI. You can track your CSI. The only reason to calculate CSI in a vinyl pool is to avoid scaling of the vinyl (highly unlikely) and scaling in the salt cell.

Use this for your recommended levels...

What Are My Ideal Pool Levels?

Use our tool to find ideal chemical levels for any swimming pool. Check TFP recommended levels on pH, free chlorine, cyanuric acid, and more.

www.troublefreepool.com

 

[MaxSpeed144]

I do have the Pool Math app, thanks.

 

[PoolStored]

Go to the gear in the upper right. Scroll to tracking. Enable Temperature and CSI. Scroll further and enable sharing with TFP. That way we can see your logs and help you troubleshoot.

With CSI tracking, if your CSI is around 0 or slightly negative, then all good. The only time to take action is if CSI is .1 or above for extended time periods. Keeping CSI 0 or slightly negative should keep your cell clean.