Excessive Borax

Jul 10, 2018
20
San Marcos, Texas
Doing the Ascorbic Acid treatment for stains. Bringing PH up and started adding chlorine. Pretty sure I added way too much Borax. Taylor PH test is purple and after adding 100 drops of Acid Demand reagent water is light yellow. I’m assuming I need significant amounts of muriatic acid but how much at a time? How long between PH tests? Thanks.
 
Assume your pH is 8.2. Use Poolmath to target 7.2. You must have a TA value inputted to calculate the amount of acid needed.

Add the acid. Circulate for 15 minutes (small pool). Test pH. Repeat.
 
HOLD UP! From Taylor test instructions 2004B, page 11:
All Taylor indicators are formulated to suppress interference from chlorine up to 10 ppm or bromine up to 20 ppm when the indicators are fresh. The amount of suppression decreases as the indicators age.

FALSE READINGS: High chlorine (>10 ppm) and high bromine (>20 ppm) can react with phenol red indicators, causing a purple color to develop, which is not part of the normal color range for phenol red.

If a purple color develops, the operator should wait until the sanitizer level has returned to a normal level before testing pH. However, some operators choose to neutralize the sanitizer by first adding one drop of chlorine neutralizer (sodium thiosulfate) to the sample. However, sodium thiosulfate has a high pH. Using more than one drop may create a "false-high" pH reading.
Also from the Extended Test Kit Directions:
High FC levels will throw off the test results. The Taylor pH reagent is compensated up to an FC level of 10. When FC is beween 10 and 20 the test will read higher than actual, the reading will be off by more at higher the FC levels. At FC levels somewhat above 20 the phenol red converts to chlorphenol red and will read as 8.2 at any plausible pH level. Chlorphenol red is sometimes used to measure pH levels between 5.2 and 6.6. Some other brands start having problems at much lower FC levels.
Based on this, I'd suspect high FC levels. What's your current FC level? If it's higher than 10, you can repeat your pH test and use one drop of sodium thiosulfate as Taylor mentions. Or wait until your FC drops naturally. But I'd hold off on adding acid until you get a correct test result.
 
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Appreciate the caution about excessive FC but I just did an Ascorbic Acid treatment after allowing FC levels to drop. I did initially add some bleach back when PH was starting to rise but discontinued that when I realized I had a serious Borax issue going on .
 
You realize the AA treatment just put the metal in the water. So should you be replacing that water? Do you have metal free water to put in the pool?

You should be increasing your FC now along with getting the ph in line.
 

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You realize the AA treatment just put the metal in the water. So should you be replacing that water? Do you have metal free water to put in the pool?

You should be increasing your FC now along with getting the ph in line.

Yes, unfortunately there is apparently iron in our water here and I've not found anyone that can offer iron free water. I've only had the spa for a year and it builds up a surface stain that I've had to treat a couple of times.
 
How much Borax did you add?
14.4 ounces by weight

- - - Updated - - -

You realize the AA treatment just put the metal in the water. So should you be replacing that water? Do you have metal free water to put in the pool?

You should be increasing your FC now along with getting the ph in line.

Just tested.

FC 6
TA 40
PH 8.2 +

Added 12 oz. Baking Soda and 2.4 oz. Muriatic Acid per PoolMath.

Would the current situation possibly give a false free chlorine reading? Water is kind of taking a greenish tone.
 
High pH and low TA, typically pretty incompatible, do not effect FC testing.

The green could be your iron precipitating.
 
First, thank you so much for your guidance mknauss! Still learning obviously, and learning to proceed with patience. I realized last night the water level was a little low, and since I was waiting on your reply about PH color, I decided to bring it up to normal and just leave things. Happy to say there was great improvement overnight and this morning’s test indicated:

FC 2.2
pH 7.2
TA 75
CH 275
CYA 75
SALT 1400

I’ve learned that I need to just be cautious about my measurements before adding chemicals and not try to move the chemistry needles too quickly.

Really appreciate this site and thanks to all of you for your attempts to help.
 
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