White crystals forming on plaster

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voidpointer said:
I have the one from the tf pro kit. I set it to 8.2 when it matches that color. I don't try to guess an in-between. I do wish this pH test had a higher level of granularity
Click to expand...

You could switch to the Taylor 2000-series comparator:


That has 0.2 granularity up to 8.0. It requires the R-0004 reagent, not sure if you are using R-0014 now.

TFtestkits sells R-0004:
tftestkits.net

R-0004 pH Indicator

tftestkits.net tftestkits.net

Or you order it from Taylor, same stuff.
 
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PB said they are coming out to look at the spa and "figure out what's going on". One thing I want to be prepared for is if they try to blame the spa damage near the waterline tile on the tile coming off the wall or something. They'll probably take every opportunity they can to blame the previous builder's poor workmanship and materials. Should plaster "rip" like that when waterline tile moves or gets "pushed out"?
 
It is possible that a movement of the tile could cause plaster to be pushed out and crack. However, the plaster usually obtains a better bond than does the tile. Most often, the plaster will pull the tile off. Tough call on that.
However, I would push the PB to focus on the multiple nodules and the wet areas surrounding the nodules. Explain to the PB that there is calcium material oozing out of very small cracks or pinholes. That is evidence that the plaster is defective. Also, water chemistry balance (whether aggressive or scale forming) does not cause very small cracks or pinholes to form and isolated and random nodules to form on those cracks and pinholes.
 
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My Taylor K-1106 test kit came in today. I took a sample of water from the SPA and got a measurement of 125ppb.

I'm not sure what my "target" range is for phosphates as I do not track this in Pool Math. But hopefully folks here can comment.

I have no idea what phosphates are so if someone could provide a simple explanation or a TFP article I can read, I would very much appreciate it. Thank you for the continued help!
 
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voidpointer said:
My Taylor K-1106 test kit came in today. I took a sample of water from the SPA and got a measurement of 125ppb.

I'm not sure what my "target" range is for phosphates as I do not track this in Pool Math. But hopefully folks here can comment.

I have no idea what phosphates are so if someone could provide a simple explanation or a TFP article I can read, I would very much appreciate it. Thank you for the continued help!
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125 parts per BILLON of phosphates is basically nothing.

Ignore phosphates and move on.

Phosphate Removers - Further Reading

www.troublefreepool.com www.troublefreepool.com
 
The background of the phosphate test was that James suggested to check for phosphates to rule out calcium phosphate scaling. In the meantime that had been ruled out already anyway by the fizz test (which confirmed calcium carbonate), and the phosphate test confirmed this, phos level is too low be be of relevance for scale formation.
 
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voidpointer said:
My Taylor K-1106 test kit came in today. I took a sample of water from the SPA and got a measurement of 125ppb.
Click to expand...
It is good to know this level to confirm that your scaling is not calcium phosphate.

The acid test does not 100% rule out calcium phosphate because it could be mixed scale, which would still fizz even if 50% of the scale was calcium carbonate and 50% was calcium phosphate.

The acid can dissolve the calcium phosphate, so just because the scale dissolves, it does not prove that it is all calcium carbonate.

1708888772749.png
 
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Thank you everyone. I read the article that ajw linked, however unfortunately this article did not help me understand phosphates and carbonates. What I did gather is that carbon & phosphorous are necessary for life, but I still am not sure what "carbonates" and "phosphates" are in layman's terms.

Reading over the "CH - Further Reading" page again, CH is a measure of calcium ions. But I do not know what calcium carbonate is. I assume carbonate or phosphate is the cause of CH being too high -- that is, that the calcium starts to clump together and form patterns/clusters on the plaster, SWG cell, and other things the water touches. I don't know which one that is. Hoping someone can teach me this stuff and help me tie it all together.

Thank you for all the help!
 
There are different forms of calcium scale.

The most common one in pools is Calcium Carbonate. That's the one what the CSI is about, which is an index quantifying how much calcium (CH) and carbonate (generally, the higher TA, the higher the carbonate content) are in the water. If there are too many calcium and carbonate ions in the water, then they will more likely combine and form scale. If there is not enough calcium and carbonate in the water, the water can dissolve them from plaster surfaces - the calcium and carbonate content needs to be balanced, or in other words the CSI should be neither too big (scaling risk) not too negative (plaster dissolving risk).

But there are also other forms of calcium scale, of which calcium phosphate and calcium sulphate can be of relevance for pools. That's why we suggested the fizz test (only calcium carbonate fizzes up in acid, the other two either don't react at all or just slowly dissolve) and to test for sulphates and phosphates.

Carbonate or phosphate are not the cause of CH being too high, they are independent parameters. But if CH and carbonate are both too high, then calcium carbonate scale can form, and if calcium and phosphate are too high (very high in this case), then calcium phosphate scale can form.

In your case, the scale has nothing to do with water chemistry parameters, the scale is coming through plaster defects from underneath.
 
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mgtfp said:
There are different forms of calcium scale.

The most common one in pools is Calcium Carbonate. That's the one what the CSI is about, which is an index quantifying how much calcium (CH) and carbonate (generally, the higher TA, the higher the carbonate content) are in the water. If there are too many calcium and carbonate ions in the water, then they will more likely combine and form scale. If there is not enough calcium and carbonate in the water, the water can dissolve them from plaster surfaces - the calcium and carbonate content needs to be balanced, or in other words the CSI should be neither too big (scaling risk) not too negative (plaster dissolving risk).

But there are also other forms of calcium scale, of which calcium phosphate and calcium sulphate can be of relevance for pools. That's why we suggested the fizz test (only calcium carbonate fizzes up in acid, the other two either don't react at all or just slowly dissolve) and to test for sulphates and phosphates.

Carbonate or phosphate are not the cause of CH being too high, they are independent parameters. But if CH and carbonate are both too high, then calcium carbonate scale can form, and if calcium and phosphate are too high (very high in this case), then calcium phosphate scale can form.

In your case, the scale has nothing to do with water chemistry parameters, the scale is coming through plaster defects from underneath.
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Thank you this is super helpful. Where does phosphate and carbonate come from?
 

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Carbonates are actually deliberately put into the water as a pH-buffer, that's the main contributor to Total Alkalinity.

TA-increaser is baking soda, scientific name sodium bicarbonate. It dissolves as sodium and bicarbonate ions in water, and via pH-dependant chemical equilibriums you also get carbonate ions.

And even without putting them in deliberately, some will build up from Carbon Dioxide from the surrounding air that will dissolve into water until the water is saturated with dissolved carbon dioxide.

There's a chain of chemical equilibriums between dissolved carbon dioxide, bicarbonate and carbonate. At pool TA levels, the water is actually oversaturated with dissolved carbon dioxide which therefore wants to off-gas (like in an opened soda water bottle), driving pH up in the process. This is the reason why TFP recommends lower TA level than pool stores.


You will always get some phosphates, they are everywhere, fertilizers, dead algae, they are part of metal sequestrants for example.

They are mainly known in pool stores as algae food, and pool stores focus on phosphate removal when dealing with algae rather than proper FC levels. TFP teaches that phosphates are a minor issue in terms of algae control and puts the focus on proper FC/CYA ratios, which renders phosphates inconsequential for algae control.

Usually, phosphates can be ignored when following the TFP method. At very high levels (which you don't have), in combination with high CH levels, they can sometimes create a calcium phosphate scaling problem, which we like to rule out when dealing with a scale affected pool.
 
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Thank you so much for the explanations! I've learned so much from this post, but that goes for every post I make here. I really appreciate this community and how helpful everyone is.

In my case, my pool has been open for about a year now and I've never had to add baking soda. I think TA from my city water supply keeps my levels high enough (although they're on the low end of my range). I assume the principle is the same -- the carbonates are coming in from the city water.

If I understand right, the TA measurement in my test kit is actually testing for carbonate levels? I always thought TA was its own chemical or something; but it looks like that's just a metric by itself and not a real thing.

Again I really appreciate everything.
 
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voidpointer said:
If I understand right, the TA measurement in my test kit is actually testing for carbonate levels? I always thought TA was its own chemical or something; but it looks like that's just a metric by itself and not a real thing.
Click to expand...

Total Alkalinity is not specifically a measure for carbonate. Total Alkalinity quantifies everything that can neutralise a "quantum" of acid, i.e. the buffering capability of the water.

The main contributor to that is carbonate alkalinity, which "counts" the number of bicarbonate ions (HCO3-) and carbonate ions (CO32-, considering that this can neutralise two quantums of acid).

But there are other contributors to TA, that's why it's called Total Alkalinity. In a pool this is mainly CYA (not the whole portion of it, that is pH dependant, and with an extra factor to account for the different units that are used to measure CYA and TA), and - if present - Borates.

The CSI formula in PoolMath internally removes the CYA and Borate contributions and calculates how much of the remaining carbonate alkalinity actually comes from carbonate ions (and not bicarbonate ions, which are the main contributors to carbonate alkalinity at pool relevant pH levels), which is what matters in regards to scaling. This gets then essentially multiplied with the Ca ion (Ca2+) concentration (i.e. the CH value) and put into relation with the solubility of Calcium Carbonate (CaCO3) to have a measure for how badly Ca2+ and CO32- ions want to combine into CaCO3. Along the way a logarithm is thrown into the formula to have the numbers in a more convenient range. There are a few more chemical details involved, but that's the gist of it.
 
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mgtfp said:
You could switch to the Taylor 2000-series comparator:


That has 0.2 granularity up to 8.0. It requires the R-0004 reagent, not sure if you are using R-0014 now.

TFtestkits sells R-0004:
tftestkits.net

R-0004 pH Indicator

tftestkits.net tftestkits.net

Or you order it from Taylor, same stuff.
Click to expand...
I'm currently in the process of ordering refill kits for my TFPro since TFTestKits is running a sale right now. Is it worth getting the taylor version of the pH test simply for the higher granularity? Honestly it would be nice to have 0.2 granularity from 7.2 to something like 8.6, but that doesn't seem to be available. Not sure which pH test to go with. I do know that when I order my TFPro refill set, I always order an extra R14 because I think I will be doing over 300 tests per year (I will test every two days, and twice on that day before/after adding MA). Any recommendation on the taylor vs TFPro version is appreciated.

Side note but I find the comparator difficult to read in house lighting that is yellow-ish in color. I always have to go outside to measure in daylight, which means testing at night is difficult. Any advice on that? Might try to find some kind of book light that is 5000K light color. Or maybe use my LED flash light. I'm sure folks here have a creative solution.
 
voidpointer said:
Might try to find some kind of book light that is 5000K light color.
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Put a daylight bulb somewhere you won't mind the otherwise obnoxious surgical white like color. The garage, basement, shed or anywhere else. I actually prefer it in my garage for all the late night tinkering and reading tiny instructions for things. I have both white and yellow in my kitchen and can turn one, the other, or both on.

For deciphering the block, I use a thumb for each hand so I only have to compare one line at a time and then it's yes, no, or freaking close enough for government work. I find I suck at picking the best of 3 when there's one above and below it.

Screenshot_20240202_093413_Chrome.jpg
 
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Newdude said:
Put a daylight bulb somewhere you won't mind the otherwise obnoxious surgical white like color. The garage, basement, shed or anywhere else. I actually prefer it in my garage for all the late night tinkering and reading tiny instructions for things. I have both white and yellow in my kitchen and can turn one, the other, or both on.

For deciphering the block, I use a thumb for each hand so I only have to compare one line at a time and then it's yes, no, or freaking close enough for government work. I find I suck at picking the best of 3 when there's one above and below it.

View attachment 556067
Click to expand...
Bud I think something might be wrong with your fingers!
 
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voidpointer said:
I'm currently in the process of ordering refill kits for my TFPro since TFTestKits is running a sale right now. Is it worth getting the taylor version of the pH test simply for the higher granularity? Honestly it would be nice to have 0.2 granularity from 7.2 to something like 8.6, but that doesn't seem to be available. Not sure which pH test to go with. I do know that when I order my TFPro refill set, I always order an extra R14 because I think I will be doing over 300 tests per year (I will test every two days, and twice on that day before/after adding MA). Any recommendation on the taylor vs TFPro version is appreciated.
Click to expand...

I think it's worth trying out options to find what works best for you.

Just to clarify: Both tests are Taylor tests.

tftestkits just resells Taylor tests. Their strength is in repackaging the reagents and deliver more useful quantities of each reagent. For example lots of chlorine reagent but not as many CH reagents. With Taylor you either buy a kit with small bottles of all reagents, or one with only large bottles (the "C" version of their kits). tftestkits essentially combined these and picks the optimum amount of each reagent to get the average user through a season.

tftestkits uses the Taylor comparator from the "residential" series that works with the R-0014 reagent:


The alternative test kits to the tf kits from Taylor - i.e. the K2006 (with small reagent bottles) and the K2006C (with large bottles) - use the 2000 series comparator that works with the R-0004 reagent:


You can order order the R-0004 reagent at tftestkits, but you'd have to buy the 2000-series comparator from Taylor (or Amazon for example). You could just buy the 0004 reagent and the comparator together - having the two reagents in different bottles may help to not get them muddled up.

See what works better for you. If you truly want to be able to measure up to pH 8.6, then you'd need a proper pH-meter. I, and others on TFP, have made good experiences with Apera. I have the more expensive PH60, but the PH20 would also be sufficient for pool applications.

For a pH-meter to work properly and reliably, they need to be calibrated with extra calibration solutions. I'd also recommend to always store it in storage solution. For me, it's worth the extra effort, I am not very good good at differentiating the red shades at the higher end. But it is important to go the extra steps required to maintain and verify calibration. Use of an un- or wrongly calibrated meter can be dangerous - it's very tempting to just take the very precise looking digital display for granted.
 
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Update:

Took a while, but I finally got the PB company to come out and look at the plaster issue in the spa. The owner acknowledges there's a plaster problem and didn't even try to blame it on me or water chemistry. So that was a huge milestone, I think. He did try to put it off on a bad gunite job (because he knows that he didn't do that part of my pool; the last PB that walked from my project did) but then I said: Well, this issue doesn't exist in the pool, so how do you explain that? He then quickly agreed and dismissed the idea. I can tell he's not thrilled with this issue but he's at least not giving me the runaround.

He says next steps will be for him to reach out to the crew that did the plaster for my pool. I guess they're going to work out what needs to be done from there. Even though I am fairly certain based on conversation here that it needs to be re-plastered, I'll let them "do their thing".

One other funny story. If you recall, I sent them a screenshot of just one of my pool logs (where I did a full run of tests on a certain day). On the way out, they complimented me for it and asked me what app I use. So, props to TFP and the Pool Math app :)

Thought you all might appreciate the update. I'll share more updates when I get them. Thanks to everyone here for the help; couldn't have done it without you all.
 
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