Calcium chunks after adding MA

[SWP Mary]

Hello All!

Happy Summer heat wave! :sun:

I have a random question about what is "normal" or what I should expect after adding MA for pH control.

I have noticed a couple of things after I add MA to my pool...1) the slight calcium line around the periphery seems to diminish (which is just fine with me as I have actively been working to reduce it) and 2) I notice there are chunks of calcium (nickel to quarter sized) that seem to come from the plumbing lines and settle on the bottom.

My ? is mostly about those chunks...does the MA "soften" any hardening in the lines and is that what is flushing out? and is this "normal" or something I should worry about?

Also...over time...would simply adding MA help reduce the faint scale mark at the waterline or do I need to be more aggressive?

I have worked to remove quite a bit of the scale already, probably a good 90-95%. Because it looks so much better I haven't been as aggressive at removing the last bit...I LOVE the thought that simply adding MA for pH over time will eliminate the rest...AND YES, I know I'm being lazy...but it is summer!

Anyway...just wondering if others have had this experience when adding MA?

Thanks in advance for your stories/experiences...happy swimming!


Forgot to add my numbers...CH runs around 850 but I live in an area with high calcium in the water so there's not much I can do about hardness...that's softened water.

 

[Texas Splash]

Hi Mary! What you're explaining doesn't seem to unusual. We already know many pool owners in the southwest struggle with very high CH water. An elevated pH can really aggravate that situation and accelerates calcium's ability to precipitate onto pool surfaces, to include your SWG. It sounds as though adding the muriatic acid helped to remove a good part of that calcium, either from some pool surfaces, plumbing, and/or the SWG cell plates.

What we always recommend is to use the PoolMath tool and look at the "CSI" row. You want to adjust pH, TA, and CH to keep the CSI number in the slightly negative range. You'll see that pH has the most dramatic (immediate) impact on that CSI number. That helps to prevent more scaling and possibly remove existing scale - as you just learned. You can read more about that on the Pool School - Calcium Scaling page.

 

[mknauss]

The calcium you are removing from the waterline goes back into solution in your water, raising your CH in the water. So eventually you need to drain water and get rid of that calcium.

The scale pieces you are seeing are most likely from your SWCG. As you exceed CH of 800 ppm, it becomes more and more difficult to manage. This fall will be a good time to do a water exchange.

 

[SWP Mary]

My CSI calculates to -0.17. So I think that is good. I believe you were right mknauss when you suggested the Calcium went up when the pool people taught me to shock weekly with TriChlor. I did not have any problems until I started doing that weekly for at least 1/2 a season! UGH...

I was going to test my outside tap water to see what that Calcium level is so I know if draining/refilling will help or not. If it is lower I will pursue draining and replacing in the fall.

In the meantime though I do have a ? about the CH testing...and the TA testing...so I can feel more comfortable that I am doing them correctly. When the directions suggest color changes from red to blue on the CH test, are we looking for when the color change first happens (which is a purple color) or do we keep adding R-0012 until we have true blue? (an aside...when I do that test I think of Sleeping Beauty and the fairy godmothers who argue over her dress color...pink, blue, pink, blue

Additionally, with the TA test, similar ? about the color of the red change. The green goes to a pink color first...is that the color change threshhold or again do we test for the true red (kind of a light brick color)?

If in fact we are testing for the first sign of a definite color change then my reported numbers are higher than they may actually be...I have been a bit confused about that since the beginning. Instead of taking the first color change I am holding out for the later "true" color change. My thoughts are that is probably correct in that the numbers reflect the problems/or lack thereof I have accordingly. But I am open to a better understanding if I am wrong.

Otherwise...I seem to be having terrific success with the TFP method...many deep appreciative thanks to all who have helped along the way!!!

 

[mknauss]

The CH test is to blue. Towards the end let the speedstir run 10-15 seconds between drops. It can take time to develop the color.

The TA test is to no change in color. So once it is red or pink or whatever and it no longer changes, that is the level.

 

[SWP Mary]

Great thanks!

Update: After testing the CH of the outside water spigot, I got a nice low 200. So it looks like draining some off and a partial refill is in order.