R - 0870 Reagent Powder

[H-12 1/2 Mike]

I have been using the TFP powder for testing my Cl this season and found the following:
A. My SWG is now having to operate at 40 to 60% whereas last season it operated at 20%. Yes, the temperatures are similar to last year and the salt concentration is also the same and the salt cell is clean.
B. Purchased some Taylor R-0870 this past weekend with an expiry date of 10/2020 and tested the water and the Cl level showed 16.5 whereas the TFP powder test showed 8.5. Ran the test again and the results were the same. I follow the Taylor procedure for testing the water.
C. I noticed that the TFP powder is much coarser than the Taylor. All pool testing reagents are stored indoors. I have been testing my pool water for 20 years and have a sparkling water in the pool. I test my pool water 5 to 7 times a week.

 

[Fuldo]

What is your CYA level and what is your FC goal? What was your CYA level last year? It's possible that your CYA level this year is lower than last year and causing greater chlorine burn-off. That and maybe your FC readings have been artificially low so you've been keeping the FC level much higher than needed and that may be another reason for high chlorine consumption.

My understanding is that the TFP powder is identical to and interchangeable with Taylor R-0870. If so, the most likely reason for the difference in readings may be the age and condition of the TFP powder. Regardless, I'd trust the high readings from the recently purchased powder and determine where you stand with FC using the CYA chart and adjust things from there accordingly.

 

[Fuldo]

I forgot to add that testing 5-7 times a week seems excessive. Once a pool is in control the owner would normally have a good feel for how things run and test/adjust much less frequently than that. This is especially so with a SWG. Your pump run time from year-to-year may also be a factor with how hard you've had to run your SWG this year.

 

[wireform]

Also to note, the blue scoops need to be clean and dry. If you have a crusty layer in there that doesn't come out, then you are not getting a full scoop of powder when you empty it into the vial. You need a heaping scoop that all empties into the test vial for the test to be accurate. Too much isn't a problem but too little won't get true results.

 

[H-12 1/2 Mike]

My CYA level is maintained at 80 and I test often because I am from a medical device background where you do frequent testing and calibration. The scoops are kept clean and dry. My target Cl level is 6 to 8. I run my pump the same as I did last year and my filter cartridges are cleaned every 90 days.

 

[duraleigh]

Mike,

IT is the SAME powder. TFTestkits orders it from Taylor. That's why it has the number R-0870 on it.....same as Taylor's number.

I have no earthly idea why you are comparing it to your SWG runtime.....how did you make that connection?

 

[H-12 1/2 Mike]

I am not comparing it to the run time. I compared it to the Cl level and the lower chlorine levels created the need for the higher SWG %. The TFP powder showed a lower chlorine level than the new Taylor powder by nearly 50%. Hence, I would have run my SWG at 20% to maintain my desired chlorine level, instead of the 60% caused by the false chlorine levels.

 

[Fuldo]

I'm assuming you've reduced your SWG output, are monitoring FC and planning to make additional adjustments to achieve your FC 6-8 goal. It will be interesting to see where you end-up. If SWG output required is still much higher than past years then perhaps an overnight FC loss test would be in order to ensure something else isn't "brewing".

 

[duraleigh]

I can only assure you that the powders are one in the same. TFTestkits uses Taylor reagents almost exclusively and the R-0870 is no exception. Sounds like you had some testing errors, perhaps an algae bloom, or wa-a-a-a y expired reagents.

 

[H-12 1/2 Mike]

I received the TFP powder earlier this year and the container had no expiration date. Upon receiving the powder I did notice that it was “chunky”. My only suggestion is that TFP put expiration dates on the powder containers. I have no overnight chlorine loss and this problem is only a test related problem. Basically a cause and effect issue. Low chlorine (false) readings causing a higher need for SWG output.

 

[TO116]

Not for nothing, but I also happened to notice a testing discrepancy last night. My TFT R-0871 reagent bottle ran out, so I did a second test using a Taylor bottle that I had, and definitely noticed a difference in the size of the drops and a corresponding FC difference.

 

[frogabog]

FWIW, I'm using up my old powder before I start with my new powder... old powder is ~5yo and a little lavender in color. I've checked it with the new powder and it's testing the same so I figured I'd use it up first.

Powder is rarely if ever a point of discrepancy with the FC/CC testing. 50% difference is very very odd.

What do you mean by chunky? Got a pic? Maybe it got some moisture in it?

You could possibly reverse engineer a known bleach/LC %. If the bleach/LC % is actually known, that is. See some old threads on testing the strength of LC for the process. Remember to use chlorine free water.

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