New TFPers Asking for Salt and CYA Advice

bmpardo

Member
Apr 19, 2024
8
East Bay, CA
Hello, everyone.

My wife and I have been pool owners for five years, and over that time, we delegated maintenance to a pool service company. We just completed a pool renovation project, and we’ve decided to maintain the pool ourselves. This website and forum have provided us with the education and confidence to take on this new responsibility. So far, things seem to be going smoothly: the pool has neither turned green nor caught fire over the last three weeks that we’ve been testing and adding chemicals. However, we’re somewhat unsure how to interpret our salt levels.

We have a freshly plastered/pebbled pool that’s approximately 12,500 gallons and chlorinated with a Pentair Intellichlor IC40. The water temperature averages 75 degrees.

Using a TF-Pro test kit, we measure 3200 ppm of salt, a salt test strip says 3290 ppm, and the pool builder measures 2950 using some sort of digital meter. Pretty good agreement. However, the salt cell only measures 2650 ppm, about 500 ppm less than what all the tests say, which is right at the boundary of the equipment’s expected accuracy. To be proactive, we started a warranty claim, and we took a water sample to Leslie’s to get supporting documentation. However, the results weren’t supportive at all: the result was 2468 ppm.

Since we can’t back up our warranty claim, and since the salt cell is generating sufficient chlorine, we’re leaning towards adding a 40 pound bag of salt to satisfy the salt cell and turn the red “Low Salt” light off. We’re looking for validation of this approach because throwing salt in the pool to trick the salt cell doesn't seem to address the root cause of the problem.

And while we’re talking, we’re wondering about our CYA levels. We’re still getting used to the subjectiveness of the test, but it seems like our CYA is somewhere around 40 to 50 ppm. Our pool builder thinks it’s 30 ppm. We want to add more CYA, but the water report we got from Leslie’s for the salt indicates that we have 77 ppm of CYA. Can we consider this measurement erroneous or should meaningful? We’ve been trying to slowly raise the level to a target of 70 pm, but are we already there? It’s the subjectiveness of the TF-Pro test that gives us pause.

In summary, we're looking for your kind feedback on adding salt and interpretation of CYA test results.

Thanks for your help.
 
A Low Salt indication on a Pentair IC, if the salt level in the pool is OK, is typically the flow sensor. They are easy to fix. If in Warranty, Pentair will replace. If not, there are replacements available on line for around $60. The Pentair brand replacement is about $120.

The reason the flow sensor shows up as Low Salt as it is the temperature sensor in the flow sensor that goes bad. Thus the IC cannot properly calculate the salt level of the water and reports as low salt.

Trust your test kit. Ignore leslies. Raise it another 10 and test 24 hours after dissolving...if your test is now 60, then keep going. If not, wait another day and test.
 
bm,

Tell me how you run your salt test.. Unlike all the other tests, you don't keep adding drops until the color stops changing, As you add drops the milky color will "flash" to a brown and then quickly turn back to milky.. The very first time in changes to brown and does not return to milky is when you stop.. Do not add any more drops and use that count number..

I assume you are using a speeds-stir type of device.. It is almost a requirement to run the salt tests.

Adding a bag of salt should make your cell work and as long at the "Actual" salt level is not above 3800, I would not worry about it.

Thanks,

Jim R.
 
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A Low Salt indication on a Pentair IC, if the salt level in the pool is OK, is typically the flow sensor. They are easy to fix. If in Warranty, Pentair will replace. If not, there are replacements available on line for around $60. The Pentair brand replacement is about $120.

The reason the flow sensor shows up as Low Salt as it is the temperature sensor in the flow sensor that goes bad. Thus the IC cannot properly calculate the salt level of the water and reports as low salt.

Trust your test kit. Ignore leslies. Raise it another 10 and test 24 hours after dissolving...if your test is now 60, then keep going. If not, wait another day and test.
Thanks for your thoughts, PoolStored.

All understood on the flow sensor. The cell is under warranty, but I have no documentation indicating a problem. The cell shows 2650 ppm and the pool store shows 2468 ppm. If a technician shows up, he'll look at those two numbers, declare everything fine, and bill me for the service call.

As for the test kit, iI trust it. But I don't trust my interpretations of the test. Therein lies my problem, but I suppose that will pass with time.
 
bm,

Tell me how you run your salt test.. Unlike all the other tests, you don't keep adding drops until the color stops changing, As you add drops the milky color will "flash" to a brown and then quickly turn back to milky.. The very first time in changes to brown and does not return to milky is when you stop.. Do not add any more drops and use that count number..

I assume you are using a speeds-stir type of device.. It is almost a requirement to run the salt tests.

Adding a bag of salt should make your cell work and as long at the "Actual" salt level is not above 3800, I would not worry about it.

Thanks,

Jim R.
Jim,

I'm glad you asked this question. It gives me a chance to confirm my methodology.

I add the appropriate amount of chromate indicator to the 10 ml sample, and then start adding silver nitrate one drop at a time. With each drop, precipitate falls out of solution to the bottom of the cylinder. The sample turns milky and with more drops the solution flashes salmon-red. The precipitate that collects at the bottom seems to change to salmon-red with each additional drop while the solution above continues flashing salmon-red and then quickly returning to milk. I stop the test when the milky solution flashes to salmon-red and stays that way. It's very clear when the end point occurs. I don't use the speed-stir device because it's one more thing to clean.

Perhaps the collection of salmon-red precipitate that I observe is actually un-mixed solution. Perhaps I'm not mixing well enough and continuing the test too long. I'll test again with the speed-stir and report back.

Thanks for your post.
 

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Also, the clean up is easy. Cleaning ammonia (10%) dissolves all the precipitate. Just rinse the vial really well after letting it soak. And try to keep the vial dedicated to only salt testing, you don’t want to cross-contaminate.
 
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Thanks, JoyfulNoise.

Our IC40 is brand new and just one month old.

I'll check on the diagnostic results and report back.

JoyfulNoise:

Solid red light for Low Salt under Salt Level.
Solid green light for Cell under Status.
Solid green light for Flow under Status.
Solid green light for 20% under Sanitizer Output.

The cell indicates a temperature between 66 and 75 degrees, which is what I would expect for today.

The cell seems fine. The problem was my testing.