cal hyp in place of calcium chloride to increase CH

abradleydvm

Bronze Supporter
Jul 28, 2019
52
Denison , tx
What is the maximum amount you can add at one time ? I was told by the “ pool guy” at Leslie’s no more than 24oz at a time and dilute in 5 gallon bucket and mix well before putting in and brush pool bottom afterwards . Pool math said o need 56 oz and I would like to put it all in if it’s safe for the pebble tech surface .

Also time frame to wait before adjusting again or adding chlorine ?
 

ajw22

Gold Supporter
TFP Guide
Jul 21, 2013
9,876
Northern NJ
What is your pH & TA and what are you lowering it to?

15 minutes between adding MA and chlorine or testing and adjusting pH again.

We don’t recommend handling acid multiple times with buckets and dilution and stirring. It creates more hazards. Just pour the acid by a return and then stir the pool water with your brush.
 

Oly

Gold Supporter
Jun 28, 2017
1,153
Fresno, CA
Be sure to pour slowly into the return stream (pump running) and as close to the water level as possible to avoid splashing. No need to dilute and mix prior, the less transfer the better. I don't brush after but cannot hurt.
I wait at least 30 minutes before adding chlorine and at least that long before testing again.
Never in the skimmer. Be safe wear eye protection and old clothing and avoid the fumes, work up wind.
 

mknauss

Mod Squad
TFP Expert
Bronze Supporter
May 3, 2014
22,397
Laughlin, NV
A pH of 8.3 (your shared Poolmath log) is not a readable value. How did you get that level?

I would suggest using a pH of 8 as Now and 7.5 as target. Your TA of 190 must be entered. Add the amount of MA stated. Circulate for 30 minutes and retest again. If pH in the 7's, use that data point as Now and 7.4 as target. Add enough MA to meet that.

Your pH will rise, especially if you are running your spa spillover each day for more than what is needed to keep it chlorinated (30 minutes or so). Test your pH every other day and adjust. As your TA falls, the pH rise will slow.
 

abradleydvm

Bronze Supporter
Jul 28, 2019
52
Denison , tx
A pH of 8.3 (your shared Poolmath log) is not a readable value. How did you get that level?

I would suggest using a pH of 8 as Now and 7.5 as target. Your TA of 190 must be entered. Add the amount of MA stated. Circulate for 30 minutes and retest again. If pH in the 7's, use that data point as Now and 7.4 as target. Add enough MA to meet that.

Your pH will rise, especially if you are running your spa spillover each day for more than what is needed to keep it chlorinated (30 minutes or so). Test your pH every other day and adjust. As your TA falls, the pH rise will slow.
The 8.3 was an error ... I use the K-1000 Test Kit...

Thank you 😊 ... I took the tfp dive this week ... removes my tabs forever and I finally found 12% bleach today .... the only other bleach was Lowe’s 10% and stored outside in the heat . I am getting more and more comfortable with the tests .

Just out of curiosity ... until I drain my CYA of 90 dictates a FCL of 7-12 .... will this bleach out swimsuits very bad?
 

abradleydvm

Bronze Supporter
Jul 28, 2019
52
Denison , tx
What is your pH & TA and what are you lowering it to?

15 minutes between adding MA and chlorine or testing and adjusting pH again.

We don’t recommend handling acid multiple times with buckets and dilution and stirring. It creates more hazards. Just pour the acid by a return and then stir the pool water with your brush.
I use pool math .... ph 8 , TA 190 ( pool store caused this ) Target ph 7.4

Thanks
 

ajw22

Gold Supporter
TFP Guide
Jul 21, 2013
9,876
Northern NJ
Just out of curiosity ... until I drain my CYA of 90 dictates a FCL of 7-12 .... will this bleach out swimsuits very bad?
No. CYA buffers most of the FC. There is little active FC and as it is consumed additional FC is released from the CYA.

I think pH 7.4 may be too low for you. Turn on CSI in PoolMath and calculate what it will be. You want your CSI between 0 and -0.3 for a plaster pool.
 

abradleydvm

Bronze Supporter
Jul 28, 2019
52
Denison , tx
No. CYA buffers most of the FC. There is little active FC and as it is consumed additional FC is released from the CYA.

I think pH 7.4 may be too low for you. Turn on CSI in PoolMath and calculate what it will be. You want your CSI between 0 and -0.3 for a plaster pool.
I have tried multiple time to get the CSI to post ... as I enter the data it calculates to .06 with ph of 7.3 and water temp 90 but it does not post to the overview .... thoughts ? What am I doing wrong ?