Using too much reagents?

[SupaDave]

Happy New Year all!!

I have finally gotten my pool balanced and looking good post SLAM. (thank TFP) During the SLAM and In the days following, I have been testing FC every day(and sometimes multiple times during the day) trying to keep FC in line with my CYA levels of 60. I find that I am going thru a lot of DPD powder and FAS-DPD reagent. With a recommended FC level of 7-9, I go thru 35-45 drops of reagent per test. Is this to be expected and I just need to bite the bullet?, or are there options? (I don't mind having to test everyday, but , you know) Also, with the Taylor kit, are two scoops of DPD powder necessary?, I think I read somewhere you can get away with one. Not a $ issue, but I see myself re-ordering reagent a lot..............

And finally, thanx again to all the good folks that give their time on this site to help us. I guess I never knew what I didn't know.

Dave

 

[Jimrahbe]

Dave,

I use the FT-100 but I think it the same basic kit.

Try using the 10 ml test, one heaping scoop, and multiply the number of drops by .5 instead of .2. Not quite as accurate but plenty close enough and uses less reagents.

Jim R.

 

[dsmith99]

The 10ml test is accurate enough and will save reagents by more than half, one scoop is plenty for the 10ml sample.

I buy the R0870 powder in the 1/4 pound container for about $32, ten to eleven times as much as the little 10 gram size and while it technically expires, most say it works fine for 3-4 years. You can buy the R0871 in the larger 16oz bottle for about $30, that's 8 times as much for about the price of about two of the 2oz bottles. Expiration is about 18 months so if you buy in the spring you can get two seasons easy enough. Store them inside away from heat and sun, even if you throw half away it ends up cheaper than buying the small bottles, you will not run out and you can test any way you like as often as you want. I bought both my kit and refill reagents from vminnovations on amazon, ebay and direct through their site and it's always been fresh and delivered quick. If you have friends or family with a pool or spa you can share and save even more.

 

[SupaDave]

Thanks all. I was concerned about the accuracy of the 10ml test, but it sounds like that will not be an issue. I take it that I will be testing everyday......
Thanks for the info, I'll start buying the reagents in bulk.

D.

 

[duraleigh]

Stop testing so much!! You are wa-a-a-ay over kill.

You have passed the SLAM and should be in maintenance mode......testing FC 2-3 times weekly.

If you enjoy testing, that's fine to do as much as you like but it certainly isn't necessary.

If you drop to the 10 ml and cut your testing by 75%, you would not be wise to buy the bulk. It'll get out of date before you use it up.

Again, there is nothing wrong to test as much as you want.....especially when you are learning. Most "old hands" will test FC often once a week because they have their pool tuned in and they KNOW what the test results will be.

I am not suggesting you try that just yet. get a season under your belt.

 

[JoyfulNoise]

I would also suggest you consider investing in a K-1001 kit which comes with a pH test (low volume R-0014 phenol red reagent) as well as the DPD only reagents (R-0001/R-0002). The DPD only test has you distinguish shades of pink and is sensitive only to FC and so it is much more accurate than the standard yellow OTO drops. If you also purchase a #9056 hi range comparator block, then you can read FC all the way up to 10ppm (but the pH side of that block need the R-0004 phenol red reagent).

I use my K-1001 for daily spot testing and only use my K-2006 on the weekend. That way I can get really accurate test results once per week and keep everything even and running smooth with quick daily checks.


Sent from my iPhone using Tapatalk

 

[triptyx]

I got a high range comparator, but I honestly can't tell the difference between the reds of the 5 and 7.5 FC boxes. Maybe the comparator is faulty, or are the reds for those two values just that close together?

@SupaDave - it's far easier and cheaper to verify your FC is ok by using the OTO test daily, and then the DPD test (which you're using now) once a week or so. While the OTO test isn't great, it's enough to validate that you haven't had an FC crash and will give you enough info to ensure your daily chlorine adds are sufficient. I'll note that, probably due to sunscreen on the littles, I had a few days this last summer where I lost far more FC than I should have, but since I was testing daily with the OTO, I was able to detect that problem and correct it without incident.

 

[JoyfulNoise]

I got a high range comparator, but I honestly can't tell the difference between the reds of the 5 and 7.5 FC boxes. Maybe the comparator is faulty, or are the reds for those two values just that close together?

Unlikely faulty, just very close shades of pink. I find that if I'm in really bright outdoor light and I hold my comparator up to a white background (I have lounger chairs with a white mesh on them) and I use my index and middle fingers to block out all other colors on the comparator, then I can differentiate fairly easy between the shades of pink as well in between the different colors themselves (I can easily spot a 4ppm shade of pink even though the comparator only has shades for 3ppm and 5ppm).

And here's a trick - you can titrate the comparator sample water with the R-0871 FAS reagent and the drop count will be almost exact to the 10mL test used in the TF-100 or K-2006 test kits (0.5ppm/drop since the comparator's water volume is 9.5mL). So, if you're unsure where the color is, you can get a very reasonable value using the R-0871. I've only done this a few times and it helped to "train my eyes" to the color shades.

 

[triptyx]

Love it, thank you Joyful! I'll give the finger trick a try.