Calcium Hardness/Fading Endpoint

[SplashDownCA]

Hello everyone, looking for suggestions on what appears to be interference of some sort when testing CH. Is there a preferred method for testing for and or removing various metals to make sure I don’t have an issue. I can’t seem to go straight from red to blue with CH test even when following the fading endpoint test method. I always get purple first. Am I supposed to see any purple as it shifts colors? Do we assume metals at this point?

Thanks to this site I think I am beginning to get a handle on taking care of my pool. I think. My current numbers are listed below with some wavering confidence in actual CH.

Wanted to share that I have tested myself and as with most people I was interested in how my testing compared to local pool stores and as I was learning wanted to see how they compared to TFP. I tried multiple big brand pool stores. After seeing the wide ranging and sometimes comical test results I was given only proved to me that they just don’t offer a reliable service you can count on. I think I was 100% convinced when a “pool expert” bashed other stores testing all while giving me results ridiculously out of whack based on common sense and my own testing. She described the wonderful chemicals she could provide to “help” me fix my non existent problem. I made the mistake of mentioning CSI/LSI and she proceeded to explain how she worked for a builder for 5 years and then the pool store for the last 6 years and has never heard of either of those things. I couldn’t help but laugh and ask if she was serious. She was. I have only been a pool owner for less than 6 months and even the most basic research you come across this information. Lmao.

FC 4.5 (added a little boost of liquid after swim day)
PH 7.7
CC 4.6
ALK 70-80
CH 390-440 (I believe I get blue at 420)
CYA 70-80
SALT 3100
TEMP 72

Sorry for the long post, also wanted to ask about the support donations. Not that it is a make or break thing but is the discount at the TFP test kits site for a discount off of 1 item only or is it a discount off of total bill? Is there an expiration date on the discount like number of days to use etc?

 

[mknauss]

You should not have issues with metals in S Cal unless you are adding copper.
CH can only be removed by water exchange or reverse osmosis.

CH test at higher levels is a challenge. Be sure you are using the 10 ml sample test.
Keep your CSI between -0.3 and 0 with your SWCG. Lowering your TA is easiest way to manage that, if necessary.

 

[SplashDownCA]

You should not have issues with metals in S Cal unless you are adding copper.
CH can only be removed by water exchange or reverse osmosis.

CH test at higher levels is a challenge. Be sure you are using the 10 ml sample test.
Keep your CSI between -0.3 and 0 with your SWCG. Lowering your TA is easiest way to manage that, if necessary.

Agreed I don’t believe I have added any copper so that part confuses me. When I enter my results into the CSI calf I get (-.15). I was being shown CSI outside of recommended levels when I had my ALK around 60 and based on temp and other current levels it seemed like ALK was the one thing it wanted a bit higher to get me back in range. Raising water temp right now to remain at a higher level wasn’t an option.

Based on the TFP recommended levels I was thinking I needed to get somewhere between 350-450 so hopefully I am still ok. I was shooting for 375. A large fluctuation in pool store CH test results (before testing myself) led me to add a little more CC than I would have liked. I have been doing the 25ML test most times but will change to 10.

Thanks

 

[mknauss]

You should not be adding any calcium. Your water is hard enough and the CH will climb with evaporation. You can manage your CSI up to about a CH level of 800 ppm and then it gets problematic.

 

[SplashDownCA]

You should not be adding any calcium. Your water is hard enough and the CH will climb with evaporation. You can manage your CSI up to about a CH level of 800 ppm and then it gets problematic.

Just curious please. When I was at CH levels of 100-130. I began adding CC to get into the recommended levels. Isn’t that what I was supposed to do? I assumed ignoring this would have caused damage if I didn’t address it. I’m not currently adding any CC to the pool.

 

[Richard320]

When I do the CH test it goes from pinkish to maroonish to indigo and finally to sky blue. Sometimes when it stalls in indigo another cycle of the speedstir will push it one way or the other. That's probably equal to 2 minutes of manual swirling.

If you get reddish floaties, ignore them. You're interested in the liquid color.

 

[mknauss]

At that starting point of CH it was wise to get it to 200 or so CH. But no more. Your evaporation will drive your CH up quite quickly. Manage CSI, not CH.

 

[SplashDownCA]

When I do the CH test it goes from pinkish to maroonish to indigo and finally to sky blue. Sometimes when it stalls in indigo another cycle of the speedstir will push it one way or the other. That's probably equal to 2 minutes of manual swirling.

If you get reddish floaties, ignore them. You're interested in the liquid color.

Thank you Richard. I will take extra time and watch color changes more closely and slow down the drops toward the end.

 

[SplashDownCA]

At that starting point of CH it was wise to get it to 200 or so CH. But no more. Your evaporation will drive your CH up quite quickly. Manage CSI, not CH.

At that starting point of CH it was wise to get it to 200 or so CH. But no more. Your evaporation will drive your CH up quite quickly. Manage CSI, not CH.

Ok. Thank you. I didn't realize that. I just thought the recommended range for SWCG/Pebble was where the CH should actually be like the other recommended ranges for water balance.

 

[mknauss]

The recommended ranges work great in the majority of the US that gets lots of rain, has soft water, and/or they winterize. Sadly, that is not true for most of areas in the southwest. So it is best to manage CSI when you have hard water.