First Test Results

pb4uswim

Well-known member
Jul 23, 2020
90
Michigan
I received my T-100 today and did my first round of tests.

Per the basic two vial test, CL was in the 5-10 range and the PH was between 7.5 and 7.8.

FC = 4
CC = .5
CH = 200-250
TA = 90
CYA = 40

Comments/Observations

Not sure about the chlorine. On the basic test kit, the color was a pretty deep yellow. I was a little surprised that FC was as low as indicated with the main test. However, it does seem basically in line with the results I've been getting from the pool store though my last visit my FC and TC were 5.6. Still, seems a bit low.

PH is not something I'm too concerned about. I got a digital meter and it just so happens that my son in law works at a plating company in the lab. They have a very sophisticated PH meter and the digital meter I have is calibrated and reading spot on. My reading was 7.6 so the basic test is in line. This is a lot different from my first basic test. I think the regents in that kit must be faulty/out of date because that reading has been consistently higher than my meter and usually read above 8. Which, is what lead me to get the digital meter in the first place.

CH - not sure about this test. It's hard for me to tell when it turns from red to blue. At 8 drops it's at least dark purple and by 10 drops, it's for sure blue. So, that's why it's 200 - 250. This is not too far off from the pool store which had me around 160. Not sure how refined this number needs to be.

TA is 90 and the pool store had me at 84, so that seems right on.

CYA has me a bit perplexed. I did the test twice (actually did all of them twice just to get the hang of things) and I got a reading of around 40. The pool store has been showing around 60. Not sure how sensitive this test is when it relies on me, a poor seeing person, to see a dot in a tube. Interestingly, it seems like I can see it pretty well. Of course, as I moved toward the window (sun light), I could see it better. I'm just not sure on this one, how far to go. Is it that you just can't make out the black dot, or it has to go away completely? As I said, even at 40 I could barely make out the dot. A couple drops after that and it was fully gone. So my CYA could even be lower than 40, but it wasn't anywhere near half way to 30.

I'm not going to do anything based on these tests. I plan on doing them again tomorrow morning and then doing an OCLT starting tomorrow night. As I said, I'm just getting comfortable with the process for now.

Regarding the process, I did get a speedspin. How do you use it? When the instructions say something like add 5 drops and then mix, do you shut it off before you add the next regent, or do you keep it spinning the entire time. I'm thinking here of the FC/CC test where you add drops, evaluate color, add drops to clear, add drops to color and then back to clear. Do you just leave it spinning the entire time? Probably no big deal, but just wondering.

Thanks for the assistance.
 

HermanTX

Gold Supporter
May 20, 2020
1,171
Katy TX
Pool Size
14600
Surface
Plaster
Chlorine
Liquid Chlorine
Thanks for the detailed update. It is excellent that you can calibrate your pH meter with higher tech equipment.
There is always lots of discussions on CYA test results. If you could see it at 40 but no longer after adding more fluid then read it as 40. I find it best to go with your first instinct when the dot is gone. Try to be consistence in how you read it, same light, same distance looking down, etc.
For the speedstir, once you measure your 10ml or 25ml then drop in the spinner (as this will raise your level slightly). Place it on the platform and let it start spinning, then just add the proper amount of drops. No need to turn on and off. It actually makes it much easier as you now focused on making the proper drop sizes and counting and not having to stop to swirl.
On CH, I count until I see the blue so yours would be either 9 or 10 drops depending on when it turned blue. Dark purple is just letting you know that you are close to the saturation level.
With regard to CL, I normally just use the DPD powder test. I find it more accurate. Once it goes clear (from pink) I use that number of drops for calculation (divide by 2 for FC). If you let it sit it tends to go back to light pink. So I just jot down the number of drops at clear then go right on to test for CC to see if it remains clear or if I need to add a drop or 2 to go back to clear. Even after CC test it may go back to light pink but disregard that. Hope this helps.
 

ship of fools

Well-known member
Nov 9, 2011
642
Albany, NY
You'll hear this repeatedly but your results (once you get the hang of it) are the correct ones and the pool store results will vary widely. Just do the tests properly and trust your results. I will buy the pH results from your son in law though!
 
  • Like
Reactions: HermanTX

PoolNewb2020

Well-known member
May 7, 2020
302
Lathrop, CA
Congrats on getting a proper test kit.
You will get a hang on your testing, just don't be tempted to go to the pool store to verify your readings. It will make you doubt your own results.

For TA and CH tests, you are looking for a color change, not the intensity of the color. Then you add one more drop and if that drop doesnt change the color, you subtract it.

CYA test gives people the most trouble, but I think it's because they are trying to be too precise with it. It is recommended to do the test outside on a sunny day with the sun hitting your back. Hold the vial by the very top, waist high when checking for the dot. You want a quick glance, no staring to find the dot. If you can't see the dot at first glance, then it's good enough.
And if the level happens to fall between two numbers, like 30 and 40, always round up to the next higher one. So the reading would be 40.
 
  • Like
Reactions: HermanTX
Thread Status
Hello , There was no answer in this thread for more than 60 days.
It can take a long time to get an up-to-date response or contact with relevant users.