CH Increase Over Winter?

[pooldewd]

After our first winter with the pool, and successfully running/using the attached spa (which worked great, I can discuss this more if interested), I opened the pool this past weekend and got it up and running.

After refilling with about 1,200 gallons using rain water collected in a cistern, I noticed my CH level had notched up slightly since I closed it last year--not less as I would have expected. I log my test results in the pool app, which should be available here.

Is this expected/normal? Where could this be coming from?

 

[PoolStored]

Is this expected/normal? Where could this be coming from?

Testing error, or reagents are going bad. Taylor accuracy is +/- 1 drop in 10.

When did you last replace reagents?

Water Testing Errors - Further Reading

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[pooldewd]

Testing error, or reagents are going bad. Taylor accuracy is +/- 1 drop in 10.

When did you last replace reagents?

Water Testing Errors - Further Reading

www.troublefreepool.com

Hardness reagent was replaced this week, the other 2 bottles were left from last year.

 

[PoolStored]

Likely just testing error.

 

[pooldewd]

Thanks I'll test again. Suppose I'm getting the same readings consistently; would this be of concern to the state of the plaster?

 

[PoolStored]

would this be of concern to the state of the plaster?

Your CSI has been slightly negative, but not below -.6. Damage typically happens when CSI is below -.6 for a period of time.

You have continually driven your pH low...as a result, your TA has come down and is now at 60. If you continue to drive pH low, you will ultimately get your TA below 50 and risk crashing your pH.

I would stop lowering pH below 7.8 and don't lower it until it gets above 8. 7.8-8 pH is perfectly fine.

Calcium Saturation Index (CSI)

How is CSI calculated? Very simple – use our PoolMath tool. To ensure long plaster life and save money, click here to learn more.

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