Water Test Question? CYA and Chlorine results.

[HuskerFan_1]

First a little history, I had to put in a new liner last fall refilled with water balanced pool added salt for new chlorine genrator.and closed all within a week. This spring I opened pool and water was clear I added dichlor to get chlorine level to shock level, added algaecide, metal out product, a clarifier, and added borax. Water is crytstal clear at this point. I also added a circupool si60 chorine generator this spring. I waited for chlorine level to drop before turning on chlorine generator. Chlorine dropped to 2ppm so I turned it on to 25% and chlorine level is increasing, pool not being used yet. Salt is at 3500ppm.

My test results with the TF-100 are in question. I have not added any cyanuric acid aside from the dichlor I added this spring. The TF-100 test shows my CYA at 80ppm and I also have an older color Q its showing 40ppm. All other tests with the TF-100 I assumed were accurate.

Took a sample to pool store because I couldn't find my borate test strips and wanted to check CYA with there test. There results:

FC .38
CC .00
pH 8.2
Alk 85
CYA 3
Borates 52


The chlorine and CYA are not matching what the TF-100 test is showing.

I thought I bought new reagents last spring and thought they were good for 18 months, so should get me through this summer. I also found my borate strips along with the colorQ tester and some other 6 way test strips. I quit using colorQ because of inaccuracy and bought the TF-100.

Anyway tested with the color Q and 6way test strips.

6 way test strips match pool store results. Color Q not so much, thats why I don't use it.

Are my reagents bad for chlorine and CYA? I've never compared results to a pool store before. I thought it was odd that the 6way strip matched pool store.

Thanks for any advice.

 

[Texas Splash]

Probably the most important thing in your message that stands-out to me is the use of Dichlor, algaecide, and clarifiers in an attempt to maintain your pool. Don't use them! Many of us have fallen victim to the pool store's recommendations and products, not to mention their in-accurate testing, and you have to break away from that. You have a TF-100 - perfect! Use it and the instructions they sent with the package along with the TFP Pool School info and/or Pool calculator. As for your readings, I'm confused because you said your TF-100 showed CYA at 80, but the store at 3? That's quite a difference. In either case, rely on YOUR test kit not theirs. Use liquid bleach/shock ONLY as recommended in the SLAM info of this site to maintain the proper chlorine level based on your current CYA. It will work.

 

[Isaac-1]

What was the water temperature, the CYA test needs to be done with the water in the general swim temperature range, you may need to let your sample warm up some.

 

[HuskerFan_1]

I can't believe the TF-100 CYA test because I just refilled the pool last fall and closed it immediately after filling. Only added enough dichlor to raise chlorine level to shock level, that is the only stabilizer I have added to pool whatever is in the dichlor. And I told pool store guy that the only stabilizer I have added was with the dichlor and his response was "dichlor is not a stabilized chlorine." My response was OOOOOOOOOK and I didn't argue.

I've been using the TF-100 for three years now and never had a problem.

As far as pool store goes I buy very little from them, I've convinced myself that I know more about pool chemistry than they do. All thanks to this web site.

I tried bleach for awhile and got tired of buying shopping carts full it. Just storing the amount I needed for my pool was too much for me.

I need to add a metal sequesturing product as I refill from my own well that is high in manganese. High manganese seemed "burn up" chlorine really fast so I was using a lot of chlorine until the manganese oxidized out and filter caught it all. This was before I knew anything and was reliant upon the pool store for advise. This goes back 4+ years and I've learned alot since then. I've since figured out my manganese problem with refill water and its not really an issue now.

I'm in the process of switching over to a salt water chlorine generator(no more bleach or dichlor for me!!!) and I'm still using the algaecide for now. Plus for what little it costs for a preventative I'll probably keep using it. The Sea Klear clarifier I use seems like a very good product and seems to make the filter work better.

I have no reason to believe that my CYA is that high. That's what it read last year before draining the pool.

- - - Updated - - -

Water temp is 80 degree.

 

[duraleigh]

A CYA test result of 3 is simply not feasible. For that matter the FC of .38 is beyond any tests capability for precision. As always, we suggest you ignore pool store results. Time and again they simply cannot be trusted. Strips are worse.

Now, let's address your CYA test with the TF-100. The R-0013 used to perform that test is chemically inert so it virtually doesn't go bad. It can be contaminated perhaps but that is a real stretch as the spout should never come off the bottle.

Please tell me what your CYA was BEFORE you added the dichlor this Spring. Can you remember how much dichlor you added?

With your help we'll get this figured out.

 

[HuskerFan_1]

Dave thanks for the response.

I didn't check CYA level because I assumed it was zero from refilling pool. I was only concerned about getting alkalinity and pH corrected and also salinity before winter, so that I could be ready to add borax at opening this spring.

I only added maybe 75 oz of dichlor this spring to get chlorine level to around 10ppm. That in turn should bring CYA up to around 8ppm. If remember correctly I may have added a little in the fall before closing but not more than what I did this spring. Took it to shock level after refilling and then added algaecide for winter that is all I've added since refilling. I wouldn't think CYA would be have been over 20ppm total after starting this spring.

OK, as far as the pool store results; I was banging my head against the wall as to why my TF-100 is not matching theres so I took a sample to another pool store. This time there test, which was a strip reader test, was consistent with my TF-100 test. pH, chlorine, alkalinity, everything was right in line. There CYA test was reading only 58ppm so I had them do the test like I do with the TF-100 and they showed around 70ppm that way. Very similar to what I was showing.

Now the question is why is my CYA level where it is?

After discussing this with the second pool store we may have come up with a solution.

What I didn't mention earlier was that when I refilled my pool last fall I trucked in my own water from a neighboring town that does not have the manganese problem.(I'm a farmer so I have my own truck that can haul about 6,000 gallons made it pretty simple to do). Where I filled the water it was hooked to the city service, and they chlorinate there water. Didn't even think about it, which shouldn't have been a concern, but the second pool store guy said they could have bought the cheapest chlorine they could get and maybe they were using a stabilized chlorine???

I know nothing about chlorinating municipal water, but it would sure take a lot of chlorine in it to get the stabilizer to that level. I have no other explanation as to where the stabilizer come from. I can't believe they would allow them to use stabilized chlorine for the water supply when the public pools are not allowed to use it.


I am now believing the results of the TF-100 I have. I was prepared to buy the R-870 and R-871 from the second pool store I went to, actually had it set on the counter before they gave me my results, after they gave me the results I realized my reagents are fine. The R-0013 is probably OK.

Sorry for the rambling, but I am still baffled at this.


Here is the results I get and had confirmed at the second pool store

FC 6
CC 0
pH 7.7
alk 85
salt 2600

The alkalinity is a little low is that going to be a problem?

The chlorine generator is reading about 3500, which is what they recommend, but my test strips show 2500 and the calculations I used for adding salt should have put it around that 2500 range.

 

[duraleigh]

I cannot think of how your CYA got to that point. CYA additions only occur in pools and, to my knowledge, never in municipal supplies.

Your TA is fine

SWG's are notorious for getting the salt reading incorrect. As long as it is generating chlorine, I would ignore it and use the calculations you have performed.

 

[HuskerFan_1]

Thanks again Dave

I am stumped too. I would have expected those CYA levels after a summer of using dichlor only, probably would have higher CYA levels.

Generator is producing chlorine.

I don't know if you've actually answered any questions I have asked here but I wanted to thank you for this site and the simplicity of the TF-100 test kit. Once I started reading this site, a few years back and a new pool owner, I ordered the kit and never looked back.

I haven't had to ask a question in awhile, but I'm in new territory with the addition of the chlorine generator.

It seems the knowledge I have gained here surpasses that which I was getting at the pool stores. Actually a friend of mine owns a pool store; not anywhere close to me, in another state, and when we get a chance to talk we talk about pools for a little bit and he finally told me "you know more about water chemistry than most of my employees." I owe my knowledge to this site and all the information here.

I just smile when friends come over and are in awe of how my water sparkles. For those friends that have pools I have told them about this site and some have ordered the test kit. They think I am an expert, but I'm just passing along information I gained here.

Thank you so much.