TF100 Test Kit

[Billtkat]

Just went to the pool store as I was going to buy stabilizer based on my result. Since I was there I brought a water sample. All the readings were close except CH was lower however I understand the TF100 adds a chlorine neutralizer so I get that - He test 155 / mine was 175 , I could live with this. However the CYA on his test was 28 where I am showing Zero this morning - I can see the dot with the tube filled to the top. Now yesterday my reading was between 20 & 30 so I am surprised it dropped all the way to zero over night - Anyway , I did not buy stabilizer and right now not sure what I should do -
I could float 1-2 tabs this week as the effects of adding on the pool math app shows CYA increase of 4.7 , which even if the pool store is right that is still only like 32-25 total CYA when they burn off. It will keep the FC around 7 pts higher which is well under shock value of 16 . Seems like a safe bet ? Pool guy did not try to sell anything, if fact said everything was good and the CYA is close to the 30-50 range that I should not add.

 

[duraleigh]

CYA does not "burn off" If you tested one day at 20-30 and the next day at zero, you have a testing error.

 

[Billtkat]

CYA does not "burn off" If you tested one day at 20-30 and the next day at zero, you have a testing error.

I would agree - This what I did
TF100 test
Pool water to bottom of label / CYA agent to top of label on test bottle . Shake and sit for 30 secs then shake again
Did in kitchen , with normal kitchen lights on ( not Outside )
Dropped solution into tube until I cannot see black dot -
Result was filled to top but could still see dot this morning.

 

[mknauss]

This works for me:
Once you have your solution ready, back to the sun, etc. Fill the vial to a line, say 80, lower the vial to your waist level and glance for the dot, you see it, add solution to the 70 line, glance, see it, repeat until you no longer see it with a glance. Then use the CYA value one step above the line you read. So if you stopped at 50, use 60 ppm CYA.

The vial is in logarithmic scale. So it is not viable to interpolate between the lines. Just use the whole numbers, such as 50, 40, 30, ....

 

[Billtkat]

This works for me:
Once you have your solution ready, back to the sun, etc. Fill the vial to a line, say 80, lower the vial to your waist level and glance for the dot, you see it, add solution to the 70 line, glance, see it, repeat until you no longer see it with a glance. Then use the CYA value one step above the line you read. So if you stopped at 50, use 60 ppm CYA.

The vial is in logarithmic scale. So it is not viable to interpolate between the lines. Just use the whole numbers, such as 50, 40, 30, ....

I tried this today and I not sure what I did wrong but I was able fill the tube and still see the dot. It was not questionable, I could see it. Because I am so unsure what is going wrong I did take a bottle of water to Leslie's and asked them to really check it , also asked if their test went to zero in case they had a limit and the answer was yes - The result was 28 just as before. They said it was , all other results were good and very close to what I got so it seems they are accurate on this one - No sales job in the visit. The process seems simple as written with just the pool water and the testing agent so hard to figure how I screw this one up.
1. Fill bottle to the bottom of the label
2. Fill with agent to the top of label
3. Mix
4. let sit for 30 secs
5. shake
6. fill tube until black dot disappears

Leslie did say I could bring my stuff and test there to see what is happening , which is nice -

 

[mknauss]

I let the mixed solution sit for much longer. But that is me.

I cannot say what is going on with your testing, mine always works. When I add 20 ppm of CYA, I see it in my testing a few days later.

 

[duraleigh]

The CYA test is completely reliable and dependable........just a little hard to interpret. Despite all the "tips and tricks", it still is a very basic test and is only difficult because there is not a sharp delineation between seeing the dot and not seeing the dot.

So, How many times have you personally performed the test and did the dot disappear or get close to disappearing during YOUR tests? Answer just that first.

 

[Billtkat]

The CYA test is completely reliable and dependable........just a little hard to interpret. Despite all the "tips and tricks", it still is a very basic test and is only difficult because there is not a sharp delineation between seeing the dot and not seeing the dot.

So, How many times have you personally performed the test and did the dot disappear or get close to disappearing during YOUR tests? Answer just that first.

When I first got the test kit a couple weeks back I did a test and the dot disappeared between 30 -20 so I recorded 30 since no markings between. About a week ago from today I put in a new pool filter as the old one was in during the start up from a new plaster job. Just thought it would be good to put in a new one as the old one caught a lot of plaster dust for 3-4 weeks. Anyway I was doing my testing this past Sunday and the CYA test showed a zero - A lot of folks said hard to see how it would go from 30 to zero and I believe it however the next 3-4 I have done , including today same result. I see the dot with the tube filled. I took it today afterwards to Leslie's and their test showed 28 , same as it did last Sunday when I tried to confirm my result of zero ) Or at least something between 0 -20 ) All my other test come out fine , just this one for some reason.

 

[duraleigh]

1. Stay out of the Pool Store. You hear it over and over but until you decide to do it, you will remain confused.

2. Trust your own testing.....it's a basic tenet of what we believe here at TFP

3. You have little to no CYA in your pool. Chalk up that first test to just being new but you have repeated your own testing 3 times and gotten zero......believe it.

4. I can't remember what your Target CYA is but use PoolMath to calculate about 10 ppm less than your target CYA and put it in your pool. Test it in a day or more and you will find you will have your target CYA (or close to it) in your pool.

 

[Billtkat]

1. Stay out of the Pool Store. You hear it over and over but until you decide to do it, you will remain confused.

2. Trust your own testing.....it's a basic tenet of what we believe here at TFP

3. You have little to no CYA in your pool. Chalk up that first test to just being new but you have repeated your own testing 3 times and gotten zero......believe it.

4. I can't remember what your Target CYA is but use PoolMath to calculate about 10 ppm less than your target CYA and put it in your pool. Test it in a day or more and you will find you will have your target CYA (or close to it) in your pool.

I was thinking 30 so I will look to add to 20. I was just worried as I had to just drain and refill my pool and not looking to do that again if I could help it.