CH testing issue swith my TF-100

[Hurricane Gio]

I tried my first CH test today with my new kit.

I could not get the water to turn blue while swirling the water. I tired twice up to 40 drops and nothing.

I noticed that a little bubble on the side of the tube turned blue, so I assume did something wrong.

Suggestions? I used the kits instructions.

 

[Bama Rambler]

Did it turn any color? It doesn't always turn real blue.

The CH test is one of the harder test to do because of the swirling involved. I use a magnetic stirrer and that makes it a lot eaiser. The endpoint with the stirrer is a lot clearer than it ever was manually stirring.

Another possibility is that your CH is over 400.

 

[Hurricane Gio]

Did it turn any color? It doesn't always turn real blue.

The CH test is one of the harder test to do because of the swirling involved. I use a magnetic stirrer and that makes it a lot eaiser. The endpoint with the stirrer is a lot clearer than it ever was manually stirring.

Another possibility is that your CH is over 400.

I used one. Like how blue?

The local store tested it a 325

 

[Butterfly]

See if this link to the test helps. Pics are near the bottom and info about fading end point, also:

http://www.taylortechnologies.com/Chemi ... ntentID=70

 

[JasonLion]

You are looking for a color change, not a specific blue. The pictures on the Taylor page linked to above are the ideal colors, but they aren't always that clear and obvious.

It wouldn't surprise me if the level was over 400. Pool store test results can sometimes be wildly wrong.

 

[Hurricane Gio]

You are looking for a color change, not a specific blue. The pictures on the Taylor page linked to above are the ideal colors, but they aren't always that clear and obvious.

It wouldn't surprise me if the level was over 400. Pool store test results can sometimes be wildly wrong.

It went to clear pretty quickly, but blue it did not. I did 50 drops and still nothing.

Now the TF-100 kit direction and the PDF from here by PaulR differ a bit.

TF-100:

Calcium Hardness test - Too much CH in all pools is harmful........vinyl, fiberglass or masonry. It can cause cloudiness in your water or scaling onto pool surfaces. Too little CH only affects masonry pools as it can leach calcium from the walls or grout. CH readings in the 200-300 range are considered ideal.
1. Rinse and fill the clear plastic cylinder to the 25ml mark
2. Add 20 drops of R-0010 and mix. Then, add 5 drops of R-0011L and mix. Red indicates the presence of Calcium.
3. Add R-0012, one drop at a time, ‘til color changes to blue. Multiply number of drops times 10. NOTE: If the pool water contains copper, add two drops of R-0012 PRIOR to adding R-0011L and continue. Count the two drops in your R-0012 total. Record.

PaulR:

Calcium Hardness Test
Use quantities in [brackets] if CH is very high
(>400) and you have trouble getting a clear transition to the blue endpoint.
1) Rinse and fill sample tube to 25ml [10ml] mark.
2) Add 20 drops [10 drops] R-0010; swirl to mix.
3) Add 5 drops [3 drops] R-0011L; swirl to mix.
Solution turns red to indicate calcium is present.
4) Add R-0012 one drop at a time, swirling continuously, 2-3 sec between drops. Repeat until color changes to blue (and stops changing).
5) The last drop that caused a change is the drop count. Multiply #drops by 10 [25] to get CH

 

[JasonLion]

If the sample changed from a red or pink color to clear then the drop that turned the sample completely clear indicates the CH level. You are looking for a color change, not a specific color.

If that is what happened, I also suspect that you were not using Taylor reagents. Some of the cheaper reagents use colors that can be bleached out by high chlorine levels so they show up as clear. The Taylor reagents don't have that problem.

 

[PaulR]

The TF-100 and my instructions are not that different. The TF-100 instructions don't include the 10ml version, and do include what to do about metal interference. There is some debate about how long to swirl between each drop of R-0012.

Are you getting a red color, and then it kind of disappears? Try holding the tube in front of a white sheet of paper (or equivalent), it might just be a faint blue. My test is always on the pale side, makes it a little hard to be sure just when it has stopped changing.
--paulr

 

[Hurricane Gio]

If the sample changed from a red or pink color to clear then the drop that turned the sample completely clear indicates the CH level. You are looking for a color change, not a specific color.

If that is what happened, I also suspect that you were not using Taylor reagents. Some of the cheaper reagents use colors that can be bleached out by high chlorine levels so they show up as clear. The Taylor reagents don't have that problem.

Jason,

I am using the regents form the T-100.
The color is changing from pink to clear around 30 drops

 

[Hurricane Gio]

The TF-100 and my instructions are not that different. The TF-100 instructions don't include the 10ml version, and do include what to do about metal interference. There is some debate about how long to swirl between each drop of R-0012.

Are you getting a red color, and then it kind of disappears? Try holding the tube in front of a white sheet of paper (or equivalent), it might just be a faint blue. My test is always on the pale side, makes it a little hard to be sure just when it has stopped changing.
--paulr

Thank you. BTW, great job on the instructions!

 

[JasonLion]

I am using the regents form the T-100.
The color is changing from pink to clear around 30 drops

Alright. That is quite unusual. Regardless, that means your CH level is around 300.

 

[Hurricane Gio]

I am using the regents form the T-100.
The color is changing from pink to clear around 30 drops

Alright. That is quite unusual. Regardless, that means your CH level is around 300.

Higher or lower would be normal?

Again, the store came up with 320 and I saw some blue as they were testing. The store I use is supposed to be reliable and are known to be good at what they do.

I will test again today and keep dropping till I see a hint of blue. But I will swirl by hand and not with the magnetic thing.

 

[JasonLion]

As I have already said, you are not looking for any particular blue. You are looking for a color change. If the sample turns clear then that is a color change. The exact rule is to add drops till the color starts changing, then continue adding drops as long as the color continues to change with each drop. As soon as you add a drop that does not change the color any further, stop and do not count that final drop.

Failing to see anything bluish when using Taylor reagents in quite unusual. But it does not invalidate the test. The test results will still be correct if you follow the procedure I just listed.

 

[Hurricane Gio]

As I have already said, you are not looking for any particular blue. You are looking for a color change. If the sample turns clear then that is a color change. The exact rule is to add drops till the color starts changing, then continue adding drops as long as the color continues to change with each drop. As soon as you add a drop that does not change the color any further, stop and do not count that final drop.

Failing to see anything bluish when using Taylor reagents in quite unusual. But it does not invalidate the test. The test results will still be correct if you follow the procedure I just listed.

thank you for the clarification. Then it stopped changing at 35 drops