Not sure if it's user error or a bad test kit

mblind

New member
Apr 25, 2025
1
Iowa
Pool Size
10600
Surface
Vinyl
Chlorine
Liquid Chlorine
TL;DR - Is it the test kit or a ID10T error on my part.

This is my second summer with a pool and I am still learning, so it is entirely possible that I am doing something wrong. My pool is a 15x30 oval with about 10,600 gallons. It is a chlorinated pool, not a salt water. I opened my pool on April 16th only because it best fit my schedule. I have been testing the water about every 3 or 4 days concentrating on my TA and pH before others. I have been using both a Taylor K-2005 drop kit and then using a test strip just to see how they compare. I like to test once a week with the drop kit and base any chemical add-ins based on that. I use a test strip once a day just to see trends. I do not make any chemical decisions based on test strips.

The results are way, way out of whack between them. The test strips consistently come back with the following: Hardness 250, TC 1-2, FC 1, TA 80, CYA 30, and pH 7.8
The drop test TC 3, FC 1, TA 180, CYA 90, and pH 8. I am most concerned about the TA being so drastically different. I took a sample to a pool store and had them test it. Here is their results: Hardness 139, TC 1.7, FC 1, TA 137, CYA 80, and pH 7.8. Again, I am concentrating on the TA and pH first before adding anything to adjust the other levels. That wide discrepancy with the TA reading between the test strips and drop kit have me baffled the most, and the pool store test result of 137 falls in between the two. Yet it is still over 40 ppm lower than the drop kit. I am questioning my method of using the test kit.

Here are my steps: Rinse test vessel obtain sample from well below the surface. Add two drops of R-0007 and swirl. Add 5 drops R-0008 and swirl to mix. I then add one drop of R-0009 and swirl. I repeat this until the mixture turns red. It takes me 18 drops to turn my water red which would mean my TA is 180. I think I'm doing it correctly, but am I missing something? Could the test kit be bad? The reagents have an expiration of 10/25 so it shouldn't be that. Should I maybe replace the reagents anyway?

I want to trust the drop kit over the test strips. This past week I have added two additions of muriatic acid of 32 ounces diluted in a 5 gallon bucket.

Thanks if you can enlighten me.
 
TL;DR - Is it the test kit or a ID10T error on my part.

This is my second summer with a pool and I am still learning, so it is entirely possible that I am doing something wrong. My pool is a 15x30 oval with about 10,600 gallons. It is a chlorinated pool, not a salt water. I opened my pool on April 16th only because it best fit my schedule. I have been testing the water about every 3 or 4 days concentrating on my TA and pH before others. I have been using both a Taylor K-2005 drop kit and then using a test strip just to see how they compare. I like to test once a week with the drop kit and base any chemical add-ins based on that. I use a test strip once a day just to see trends. I do not make any chemical decisions based on test strips.

The results are way, way out of whack between them. The test strips consistently come back with the following: Hardness 250, TC 1-2, FC 1, TA 80, CYA 30, and pH 7.8
The drop test TC 3, FC 1, TA 180, CYA 90, and pH 8. I am most concerned about the TA being so drastically different. I took a sample to a pool store and had them test it. Here is their results: Hardness 139, TC 1.7, FC 1, TA 137, CYA 80, and pH 7.8. Again, I am concentrating on the TA and pH first before adding anything to adjust the other levels. That wide discrepancy with the TA reading between the test strips and drop kit have me baffled the most, and the pool store test result of 137 falls in between the two. Yet it is still over 40 ppm lower than the drop kit. I am questioning my method of using the test kit.

Here are my steps: Rinse test vessel obtain sample from well below the surface. Add two drops of R-0007 and swirl. Add 5 drops R-0008 and swirl to mix. I then add one drop of R-0009 and swirl. I repeat this until the mixture turns red. It takes me 18 drops to turn my water red which would mean my TA is 180. I think I'm doing it correctly, but am I missing something? Could the test kit be bad? The reagents have an expiration of 10/25 so it shouldn't be that. Should I maybe replace the reagents anyway?

I want to trust the drop kit over the test strips. This past week I have added two additions of muriatic acid of 32 ounces diluted in a 5 gallon bucket.

Thanks if you can enlighten me.
The test strips are garbage and can’t be trusted. Don’t bother using them.

It’s better and safer to add acid directly to the pool water. Slowly in front of a return jet.
 
I have been using both a Taylor K-2005 drop kit and then using a test strip just to see how they compare
They are about the same accuracy, which is not very. Ans both are vague comparison tests without an actual value.

You need a fas/dpd test for actual, and reliable FC values.

I am concentrating on the TA and pH first before adding anything to adjust the other levels.
Sounds poolstore-y. Worry about the long term things while the short term thing swamps you. (High CYA and low FC)

You'll need to drain to lower the CYA and refilling will throw off your TA/Ph. Abandon that for now.
Could the test kit be bad? The reagents have an expiration of 10/25 so it shouldn't be that. Should I maybe replace the reagents anyway?
Was it stored climate controlled ? If so they're good for a long time.