Frustrated......pool chemistry

[kjdo]

We have had our pool open since April 2012 (built October 2011). We had one episode of cloudy water, shocked it, got the problem fixed. Or, at least with our test strips, checking water at two different pool locations in town, etc. Then as the weather started to cool off and we turned the heater on, kept the cover closed more, we seemed to start having problems. Really the biggest thing we had to do this summer was add muratic acid (spelling?) to decrease the pH, regularly add Phos Free (maintenance doses). Then even though it was not cloudy, I did a titration test for FC/TC/CC and felt like we had a problem. I took pool water to be checked and was told we had CC and we shocked the pool. Then we have tested the pool water at the pool shop (2 different ones) several times, have added alkalinity increaser, calcium, etc. I just didn't like what they were telling me, so I found your website, ordered TF-100 which arrived today. Testing complete and I need help....

FC = 35
CC = 0
TC = 35
T/A = 130
CH = 130
CYA = 60
Salt = 4000
pH = 7.8

 

[jblizzle]

Welcome

How does your water currently look?
Are you only using the SWG for chlorine? What were you using to "shock" {which is likely different than what we mean here ... see Pool School if you have not}

The only things of note:
1. CYA is slightly low for a SWG, but not much of a problem
2. FC is too high (shock level is only 24ppm ... this could be fading your liner) ... turn the SWG off and let it drop.
3. pH is borderline high ... the SWG will tend to make it drift up, acid drops is as you know
4. TA is a little high ... if you work to lower this (see article in Pool School), if may slow the rate at which the pH goes up.

Really, besides the high FC, things look pretty good assuming the water is clear.

Also realize, that there is no point worrying about phosphates or adding algaecides or anything like that which just makes the pool store money.

With a liner, there is no reason to worry about a low CH level either.

 

[kjdo]

Water looks great.
I have read the pool school but unfortunately after the shock. The shock I used was what the "pool company" asked me use. Liquid pool shock.
I will turn off the SWG. I will add muratic acid which should decrease the pH and the TA.
We live in Indiana, so it is getting cold here. We have not "winterized" and we are planning not to close the pool until after Thanksgiving. However, we are not heating the pool right now and the cover is closed. So, I don't know if the FC will drop. The people who built our pool were the ones who told us to watch the phosphates, so I'm not sure what I will do with that regard. I have never added an algaecide.

There has been a time when the skimmer had slimy stuff at the water level, that is not present now. I don't know what that was. Thank you for your input.

 

[jblizzle]

Well ... at least you used the liquid pool shock ... which is really just higher strength bleach and does not have the side effects of the powders.

When the pool is covered and the water is cooler, you will need to still keep an eye on the FC and either reduce the pump run time or lower the FC output or both so that it does not get so high.

Next year is going to be a breeze now that you found us

 

[kjdo]

OK. Today it was beautiful here, sunny, etc. I had the day off, so I opened the pool and put the tiger shark in to clean. I now think the water looks dull/cloudy. It has been awhile since I used the tiger shark because we hadn't been in it. Will that do it? There were a lot of dead bugs in the device when I opened the compartment. I retested some of the readings and they are improving, nothing is worse.

FC - 29
cc - 0
TC - 29
TA - 120
pH - 7.8.

So chlorine is coming down as is the TA. I plan to recheck the pH, TA and chlorine again tomorrow unless you tell me different.

One other thing.....unless I missed it, no comment made regarding black or green slime around the water line in the skimmer basket that has been present in the past.....not there now.

Thanks

 

[jblizzle]

Slime could have been algae or sunscreen/lotion residue ... chlorine will take care of it.

TA will not usually drop unless you add acid ... accuracy of the test is +/- 1 drop so 10ppm.

If you had not brushed or cleaned in a while, there could be dirt/dust that has settled. Brushing or running the cleaner could certainly stir that up and make the water look less clear.

 

[UnderWaterVanya]

As you add acid the TA will slowly drop. Yours is higher than you want with an SWG the only real impact of this is that you will see pH rise faster and use more acid - but that in turn lowers TA so it is self correcting.


- Sent using Tapatalk

 

[kjdo]

I have a question about the TF-100 Kit and the K-1000 pH test kit that came with it. I have two other pH test kits that are "titration" methods and one says it is not accurate with high chlorine and the other actually has me adjust the water being tested (one drop for every 2 ppm of chlorine) before testing the pH. Why do I not have to adjust the k-1000 kit before testing the pH? Just wanting to be sure my pH reading is actually correct. FYI - the obsessive compulsive side of me has tested with one of the other kits and found a very similar pH reading for the K-1000 and the other kit, but I am curious.)

 

[Bama Rambler]

The K-1000 is buffered for some chlorine but it's not accurate above about 10 ppm FC.

 

[kjdo]

OK. I'm not making much progress. These are my tests for the last several days. At the bottom of each day if the action taken.

Date 10/3/2012 10/4/2012 10/5/2012 10/6/2012 10/7/2012
FC 35 29 31.5 29 27
CC 0 0 0 0 0
TC 35 29 31.5 29 27
TA 130 120 120 120 130
CH 130 not tested not tested not tested not tested
CYA 60 not tested 60-80 not tested 70
SALT 4000 not tested not tested not tested not tested
pH 7.8 7.8 7.8 7.8 7.8
Tested at 3 p.m. Tested at 3 p.m
ACTION Turned off SWG based on pool calculator
Added Acid Added Acid Called for 11 oz of muriatic acid and I added 10 oz
Opened pool Raining so didn't open Open all day and night
Called for 13 oz of stabilizer (by weight) and I added 6 oz (by weight)

I now wish I han't added stabilizer (and I didn't put in a sock so I could remove it) since it sounds like it is going to prevent the chlorine level from dropping. I have the pool open day and night and it is getting cold here, the nights are supposed to be cool but it is supposed to be sunny, so I'm going to leave cover open day and night for the week. I don't know why the TA went up unless it's just operator error in testing process. But, the pH isn't changing. Today the pool calculator is saying to add 21 oz of Muriatic acid, so I guess I will add what it is recommending since I'm not seeing progress. I am so used to adding less than what anyone says to add because I don't trust the results. Any suggestions beyond, leaving cover open and adding acid?

 

[kjdo]

So sorry, I had it in an excel spread sheet and it looked good when I posted it, then it got all bunched up, so it's hard to see what is what....

 

[duraleigh]

OK. I'm not making much progress.

It is not quite clear to me what you are trying to do. What does your water look like now? Tell us more about your intentions.....aren't you about ready to close?

 

[kjdo]

We are hosting Thanksgiving for 24 people and we had intended to keep the pool open until then, heat it up and swim.......however, we have had a bad last month with pool chemistry. We were taking pool water to local pool store for testing and we had CC and according to their reading, very very low alkalinity. We shocked the pool with liquid pool shock (4 gallons) and added I don't know how much Aklalinity up......... I wasn't comfortable with their readings, which kept saying our alkalinity was low.......so purchased the TF-100 ..... We now have
Date 10/7/2012
FC 27 down from 35 on 10/3
CC 0
TC 27
TA 130 (same since 10/3 in spite of acid added)
CH not tested
CYA 70
SALT not tested
pH 7.8 (same since 10/3 in spite of acid added)

Are these settings OK to CLOSE the pool? At this point, I think we are just going to close the pool rather than fight with it for 6-8 weeks. I assumed I should get the chlorine level, pH and Alkalinity levels all down before closing.. So, that is what I am trying to do

 

[UnderWaterVanya]

We are hosting Thanksgiving for 24 people and we had intended to keep the pool open until then, heat it up and swim.......however, we have had a bad last month with pool chemistry. We were taking pool water to local pool store for testing and we had CC and according to their reading, very very low alkalinity. We shocked the pool with liquid pool shock (4 gallons) and added I don't know how much Aklalinity up......... I wasn't comfortable with their readings, which kept saying our alkalinity was low.......so purchased the TF-100 ..... We now have
Date 10/7/2012
FC 27 down from 35 on 10/3
CC 0
TC 27
TA 130 (same since 10/3 in spite of acid added)
CH not tested
CYA 70
SALT not tested
pH 7.8 (same since 10/3 in spite of acid added)

Are these settings OK to CLOSE the pool? At this point, I think we are just going to close the pool rather than fight with it for 6-8 weeks. I assumed I should get the chlorine level, pH and Alkalinity levels all down before closing.. So, that is what I am trying to do

Take a deeeeeeeep breath. Repeat after me:
I can take charge of my pool chemistry and laugh in the face of pool stores from now on!

Feel better? The Pool store may or may not have been correct - but they obviously gave you a bit of wrong advice on how much TA increaser. The good news - who cares! It's not a very important item when it comes to the chemistry of your pool. I don't mean that it isn't important to measure it and understand it - but unless you have scaling issues - let it come down on it's own by adjusting your pH over time. It may take a long long long time - but it will happen eventually.

Speaking of pH - you can't measure it reliably at > 10ppm FC. The test reads high - I'm surprised you don't see 8.2 but chances are your pH is fine. Until you get below 10ppm you won't need to test it and it just doesn't matter right now.

FC of < 28ppm is under your shock value and safe to swim in. You are already just below there and could swim to your hearts content right now! If your goal is to swim at Thanksgiving - you're not going to have too much problem with that at the rate you are going. You've lost 8ppm in 5 days - and even if that slowed down to 1ppm every 5 days that would still drop the FC another 9-10ppm before company arrived. More than likely you'll have to kick the SWG back on before too long just to keep it from going below your minimum.

So what are you worried about?

Should you want to close anyway, the only problems I see with closing are:

1) You will lose out on this dream of swimming in warm water at Thanksgiving.
2) Your pH can't be adjusted with FC > 10 and could be low or high. Leaving the pool for an extended period of time with too high or low would not be good - it would be best if you knew the pH and adjusted it accordingly before brining it back to shock levels for closing.

 

[kjdo]

I have a 5-way test kit that has a chlorine/bromine neutralizer compound that is added to the pool water in the test tube. One drop for every two ppm of chlorine. Then you add phenol red and test. According to that test kit, the pH is reading 7.8. This test kit has an äcid demand test as well. You add drops to get to the desired pH reading and based on the number of drops added, it tells you by a nomogram how much acid to add. Anyway, very long story to say I am aware of the problem with pH when the chlorine level is too high, but I didn't think I was supposed to ignore those readings (pH and Alkalinity) while getting the chlorine under control.

 

[duraleigh]

It is fine to close the pool just like it is. pH reads falsely high in the presence of FC over 10ppm so, as UWV suggests, your pH is probably just fine.

If you decide to warm it up to swim, that's fine, too.

Leave your chemistry alone and enjoy your Turkey Day Swim or close the pool....either way your chemistry is adequate.

 

[UnderWaterVanya]

I have a 5-way test kit that has a chlorine/bromine neutralizer compound that is added to the pool water in the test tube. One drop for every two ppm of chlorine. Then you add phenol red and test. According to that test kit, the pH is reading 7.8. This test kit has an äcid demand test as well. You add drops to get to the desired pH reading and based on the number of drops added, it tells you by a nomogram how much acid to add. Anyway, very long story to say I am aware of the problem with pH when the chlorine level is too high, but I didn't think I was supposed to ignore those readings (pH and Alkalinity) while getting the chlorine under control.

I have both Taylor (which has phenol red with something added for chlorine tolerance) and Poolmaster which uses a separate chlorine neutralizer - the Taylor kicks the Poolmaster's butt. I say this based on tests using both. If the water has low levels of FC (< 2) the two read similar but with higher FC (say > 5) the Poolmaster gives abnormally high results. I have tested the chlorine neutralizer by using the OTO test on the treated sample water to verify the drops needed to neutralize the Chlorine. Typically it only needed 1 -2 drops.

Sounds like yours works better than Poolmaster however. What brand is it? Richard (chem geek) has indicated the neutralizer skews the results up itself.


- Sent using Tapatalk

 

[kjdo]

The brand is Kem-Tek, I think I purchased it on line somewhere.....probably Amazon. I am going to stick with Taylor products but I have this one and will use for comparison. I do have a really hard time reading the red/pink colors. Who knows, maybe it is 8.2 and I'm reading it 7.8. ?!?!?!?!? I don't think I am color blind, but have a hard time separating. I wish they had a "titration test"for pH, I seem to do much better with those, watching for a color change.

The Chlorine is down another point today, so I'm happy, I'm not testing anything else until it gets below 10......I guess at that point I'll turn the SWG back on.

 

[UnderWaterVanya]

The brand is Kem-Tek, I think I purchased it on line somewhere.....probably Amazon. I am going to stick with Taylor products but I have this one and will use for comparison. I do have a really hard time reading the red/pink colors. Who knows, maybe it is 8.2 and I'm reading it 7.8. ?!?!?!?!? I don't think I am color blind, but have a hard time separating. I wish they had a "titration test"for pH, I seem to do much better with those, watching for a color change.

The Chlorine is down another point today, so I'm happy, I'm not testing anything else until it gets below 10......I guess at that point I'll turn the SWG back on.

I'm in the same boat on the pH test... I've gotten ok at it but it really can be difficult at times. I have good color vision.

-sent with Tapatalk 2

 

[kjdo]

Is there anyway to check the pH and Alkalinity when the chlorine level is still too high(19)? I have been checking at least the chlorine level daily and it does seem to go up and down. The SWG is off. The cover is off most of the time, but we are expecting a lot of wind in the next 48 hours, so we have closed it to keep leaves, etc. out of the pool. Chlorine level seems to go up when the cover is on (even if I check it hours after opening the cover). Also, does temperature have any effect on the chlorine level? Anyway, since the chlorine level is still too high I can't get an accurate pH and Alkalinity check. As these two seemed to be going up steadily, yesterday I did add 1.5 pints of muriatic acid. There was a slightly decrease in the alkalinity, (now 130 so still too high, it was 150). No affect on the pH (I am getting 7.8, but according to acid demand test on the Kem-tek 5 way test it wants me to add 4 pints of acid----which of course, I am not going to do).....but we are still wanting to use the pool at Thanksgiving and I am trying to get the Chemistry right. I didn't have all this trouble this summer----was it because the pool was open and the sun was shining and it was hot?