CYA test ~~ Trouble with view tube DOT .....

Jun 12, 2009
1
Hello.

I am new to the forum and attempting the BBBmethod....

I have purchased the Taylor TF-100 kit ~~ but I am having major trouble understanding and performing the CYA test. I have tried it a couple of times now and I am not "getting" it, as they say. :rant: After mixing the correct amounts of the pool water and the chemical and proper wait time, as I am holding it at waist level and pouring the mix in the viewing tube, I don't understand what is meant by "when you no longer can see the black dot" ~~ what do they mean?? Do they mean because of cloudy water (because mine is very clear), or do they mean where ever I am looking, that the dot image should be distorted and move, or what?? And where should I be looking for that dot anyway ?? Straight down into the tube while holding at waist level, or while at waist level, looking thru side of tube?? I really appreciate any help at all with this, as it is going to get quite costly while I keep practicing, trying to "get it". Thank you for your help. :wave:
 
Hi, Denise,

We can help. First off, I am too embarassed to tell you the mistakes I first made with the cYA test......let me just say it was worse than what you've done.

The CYA test measures cloudiness. If you have CYA in your pool, the reagent (R-0013) turns the solution cloudy and the dot will disappear as you fill the tube up.

Your problem is you have no CYA in the pool so the solution never turns cloudy.

Even when you fill it to the top, it stays clear and that's because there is no CYA in your pool.

The test is not intuitive. Post back if you've got more questions.

Also post your other test results for folks to look at. With no CYA, you will be/are going thru chlorine very quickly so we need to get CYA in there soon.
 
It is the most difficult test to master, so don't feel alone. After years of doing it, I still question myself and I do trust my local Leslie's on this test, so I double check my results with them. I don't trust a lot of other pool stores, but I have had good luck with my Leslie's.

You are to look down into the tube. When it is empty, you see the bottom has a large black dot, there. When you add your test sample (which has been mixed with the drops, etc), at some point the the black dot should get harder and harder to see, the more of your sample that you add. Once you cannot make out that there is even a black dot on the bottom of the tube, you stop and read the level.

I know there is a link somewhere that shows some really good pictures, but I don't have it handy, myself. I'm sure one of the regulars will pop in shortly to give you the link.
 
This test really is a pain and the little kits take some getting use to. We use a 50ml test setup and go through about 1.5 gals of test solution per year. The larger volume test works much better and save us money over the season due to more accurate test results.

You slowly pour the mix into the viewing tube and look straight down from the top. The solution should be cloudy. Kind of a milky off white. If your solution is clear, you either have done the test incorrectly, you have too little (<10ppm typically) CYA or do not have any CYA in solution.

To practice this test, take one of your tablets, break a chunk off and crush it in an old rag with a hammer. Try to get it pretty fine. Mix with a cup of hot water and let dissolve. Then run the test after the stuff dissolved. You should get enough CYA to give you a good visual on the test. The trichlor CYA tablets run typically around 50% CYA.

An 8oz cup will give you 240ml of water, so plenty for testing.
 
wejones said:
This test really is a pain and the little kits take some getting use to. We use a 50ml test setup and go through about 1.5 gals of test solution per year.
Which is not cost effective for the average pool owner. Please keep that in mind.


You slowly pour the mix into the viewing tube and look straight down from the top. The solution should be cloudy. Kind of a milky off white. If your solution is clear, you either have done the test incorrectly, you have too little (<10ppm typically) CYA or do not have any CYA in solution.

To practice this test, take one of your tablets, break a chunk off and crush it in an old rag with a hammer.
You are making the assumption the OP is using trichlor. They never stated this and if they are not you might be confusing a newbie.

Try to get it pretty fine. Mix with a cup of hot water and let dissolve. Then run the test after the stuff dissolved. You should get enough CYA to give you a good visual on the test. The trichlor CYA tablets run typically around 50% CYA.
Actually, dichlor is more of a 50/50 mix (for every 10 ppm FC added by dichlor 9 ppm of CYA are added -- 9 parts out of 19). Trichlor is more of a 1/3 CYA to 2/3 Chlorine mix (for every 10 ppm FC added trichlor adds 6 ppm CYA -- 6 parts out of 16).
An 8oz cup will give you 240ml of water, so plenty for testing.
 
Interesting post and Butterfly thanks for the link. My CYA may be a little higher than I think.
See, I can still see the black dot at the bottom of the third photo in the link. With that being the case my number may actually be just a bit higher but not much. I was expecting the dot to go away completely but it doesn't, it just gets hard to see clearly. So, this helps me and I plan to test again to see what I find.
 
Also... while you are trying to get it right, you don't have to mix a new solution. Pour yours back in the bottle and try again. I was doing the same as you exactly and I went through the reagent very quickly, then I read on here that you can do it a few times with the same solution (just for the purpose of seeing the dot or not) . Testing on a different day would require a new mixture.

Please correct me if this is wrong info.
 
dattia, you have it right. You have about five minutes after mixing the CYA test solution during which time you can pour it into the view tube to see the level, and still pour it back into the mixing bottle and try again. You can continue practicing for more than five minutes if you want, but the result will start to drift from the correct value.
 

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gsmornot said:
Interesting post and Butterfly thanks for the link. My CYA may be a little higher than I think.
See, I can still see the black dot at the bottom of the third photo in the link. With that being the case my number may actually be just a bit higher but not much. I was expecting the dot to go away completely but it doesn't, it just gets hard to see clearly. So, this helps me and I plan to test again to see what I find.


Exactly! Wow. I've been reading it wrong. oops.

Looks like I'll have to retest with this "Still see it a tad" method.


So much for my cya being at 40.
 
Lazyman said:
Exactly! Wow. I've been reading it wrong. oops.
No, the dot should completely disappear. reebok already explained this correctly.

The dot disappears completely. You can still see the outline of the white circle joining the tube wall at the bottom of the tube, which is larger than the black dot. No hint of the black/white boundary should remain.
 
Well, call me crazy but I can still see the dot on my screen. It's faint but the dot is there.
I see the outline on the bottom of the tube as well so my comment was about the fact that I'm looking too hard for the dot.

I don't know, the more I look at it the more I wonder if what I see is what I know to be there. I can say that when I do the test at home it has not been as cloudy as the sample shown here. So, the point here is thank you for the info and I plan to retest tonight to see what I get. I do my full testing on Sunday nights.
 
ok, you're crazy :) if you don't believe the manufacturer's pictures, then you shouldn't believe the test at all. but it's probably not a huge deal, just do what you think is right and try to get a second opinion also. you'll probably come out in the ballpark. a pool store test can help confirm, though they can be inaccurate also.
 
:lol:
I believe their pictures. I see that I was doing it wrong and after my test tonight I see that I am closer to 50 than 40 on CYA. My original technique would allow me to see the dot because I held it a little too close. I've got it covered and crazy is right.
 
Just to clarify for anyone that might still be confused...if you look at the first two pictures in the Taylor link and notice the size of the dot and then look at the third picture at what 'appears' to be the dot, notice it is about twice as big and is actually the walls of the view tube. The dot has totally disappeared. If you look again at the middle picture you will see this 'ring' around the dot. It is NOT the dot.
Hold the tube at waist level in open shade outdoors when doing this test. It will help a lot!
 
Hi there,

I just found that thread and have a sub-question regarding the CYA test. I'm conformtable with the notion of seeing or not the dot at the bottom of the tube. My question is more about delays, here is an example that will help to understand my subtle, but important question, about CYA test result:

1) I have done my mix and start to poor (it's more a spray) the liquid in the view tube.

2) As I spray the mix (liquid), I still see the black dot, so I continue to spray.

3) A bit later: as I spray the mix, I now cannot see the black dot anymore, it has totally disappeared, so I stop spraying the mix.

4) As I just stopped to spray (1 or 2 seconds ago), the liquid in the view tube starts to get clearer (less fuzzy/cloudy) and then I start to see the black dot again (just a bit, but I see it).

5) I then re-start to spray the mix in the tube for few seconds and then the dot disappear again, but this time it's gone for a long while.

My question is:

When should I read the measure for my CYA, at step 3 or 5?

To me the measure could vary a lot (from 90 to 65 for instance) between the two steps. I'm sure that many people read at step 3 and many others read it at step 5. In both steps, the black dot is gone (disappered), but in step 3, as soon as you stop to spray, it comes back quickly (around 2 seconds). In step 5 it takes a longer while to come back.

BIC
 
I think if you're "spraying" the mixture you may be entraining some air in the mix and as it de-entrains that's causing the liquid to appear to "clear up". I gently pour the mixture into the view tube until I can't see the dot anymore. Then I pour it back into the bottle and repour it in the view tube two more times to see if the results agree.
 
Bama Rambler said:
I think if you're "spraying" the mixture you may be entraining some air in the mix and as it de-entrains that's causing the liquid to appear to "clear up". I gently pour the mixture into the view tube until I can't see the dot anymore. Then I pour it back into the bottle and repour it in the view tube two more times to see if the results agree.

I hve the TF-100 Kit and the bottle provided to mix the water pool and the Reagent R-0013 has a cone cap (cap with a cone shape with a little hole at the top). I thought that if the bottle has such a cap it's for spraying the mix slowly into the tube. I find it very usefull for that.

I tried to simply poor the m,ix in the tubve (as you described) and I get the same result (same CYA level), so it may not be that important to spray or psimply poor.

You didn't answer my question though, do you read at step 3 or 5? :mrgreen:

BIC
 

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