Testing for MPS & CC w/ColorQ

[JTDL]

Hi Folks... I'm a 2nd year pool owner but 1st year pool boy as I fired the pool service.

I'm currently testing with a ColorQ7 and I've used non-chlorine (MPS) "shock" thus far. After reading the site, I've learned this isn't really going to impact CC and that my DPD3 testing is in error. Adding more MPS is not the right action, which is what I had been doing to reduce what looked like high CCs.

I now have the Taylor DEOX R-0867 reagent but I don't know if I'm using it correctly with the ColorQ. This is the process I've used and results..

1. ColorQ testing (no reagent)
FCL 2.82
TCL 3.02
PH 7.7
ALY 131
CH 131
CYA 97
Results in CC of 0.20

2. ColorQ with DEOX
a. blank meter with same sample
b. Standard FCL test with DPD1 and DPD2 (five drops each)
c. Add five drops R-0867
d. Add five drops DPD3
e. invert once, tap to remove bubbles (no stir or shaking)
f. Read TCL
FCL 2.65
TCL 2.65
Results in CC of 0.00

I think I can conclude that I actually have CC= 0.00 and MPS = 0.20. Is this correct?

BTW... I now have some education (thanks pool school) and awareness that these results show my CYA and FC are out of sync. I welcome any general input.

thank you in advance!

 

[jblizzle]

Welcome to TFP!!

I am not sure how to answer your question, but this post has so many things in it counter to our teachings I am not sure where to start.

1. We are not very fond of the ColorQ as it has proven to be unreliable and has some limitations (like FC < 10ppm)
2. We do not recommend adding metals to the water like the Frog Mineral pacs do
3. We do not recommend using trichlor exclusively for chlorination like your Frog feeder does (this is why your CYA i2 now too high)
4. We hardly ever recommend the use of algaecides, which is what I assume the Frog BAM Algae is
5. We very rarely recommend the use of MPS as there is just no need in outdoor pools
6. We never "shock" our pools on some schedule. We maintain the correct FC level as a function of our CYA level (see the FC/CYA Chart) and if there happens to be a problem develop, we follow the ShockLevelAndMAINTAIN Process.

So there are the highlights. Feel free to ask questions. Glad you found us

 

[chem geek]

I think I can conclude that I actually have CC= 0.00 and MPS = 0.20. Is this correct?

To the degree that the ColorQ is reporting correctly, yes you are correct.

Also, if you were to find actual CC of 0.2, that would not be a problem. In most pools on this forum, the CC is 0.2 ppm or less, but most people just measure using a 10 ml water sample so can only tell that it's 0.5 ppm or less. CC is rarely an issue in an outdoor residential pool exposed to sunlight and where the appropriate FC/CYA level is used.

 

[JTDL]

Thank you both for the quick replies.

I'm not able to color match well so I had high hopes for the ColorQ. Time to order a test kit and to read up on switching from the frog 'system'.

For now, I guess I need to drain some water to get the CYA levels down so my FC is effective. Thanks!

@Chem Geek, can you confirm five drops of the DEOX is the right amount?

 

[chem geek]

For the Taylor K-2042 that uses the R-0867 deox reagent and is used in the Taylor FAS-DPD tests, they use 1 ml of R-0867 deox reagent for a 25 ml water sample size (see their instructions). The Taylor bottles have around 24 drops per ml. However, I don't know your sample size but I suspect that 5 drops is not enough unless your MPS level was low (which it seems to be).

As for the ColorQ, it does worst with the CH test when it is higher, typically measuring too low when the CH is above 300 ppm. The CYA test is sometimes flaky. The other tests tend to be OK, but if you read threads on the ColorQ you'll find some mixed results. It's not terrible and for those who are color blind there's probably not a better reasonably priced choice.

 

[jblizzle]

The only test in the recommended kits that requires a color match is the pH. The CYA requires you to add a solution to a tube until you can not see a black dot and the rest all require counting drops until there is a color change in the solution.