What is the "cause" of PH rising and CC rising?

Tuckerclan

Well-known member
Sep 7, 2018
99
Kansas
You can see from my logs, I have now been using lower amounts of Chlorine (good) but I'm still wondering why my CC is between .5 and 1.5. It changes almost daily. Also, I tried ti lower my TA by using Muriatic acid. I added what was suggested (3 cups) and it lowered a bit, but not much. I did it again, no change, then added a cup or 2 every other day. Still not much change. Now the gallon is gone, but my PH never really dipped below 7.5. Never saw 7.2. Am I just worried over nothing? Seems like when 1 balances another goes askew. But what is the CAUSE of PH never lowering?
 

thetekgeek

Bronze Supporter
Jun 8, 2018
255
Nebraska
What is your TA? High TA will drive the PH up faster. How long after adding acid are you testing?

CC is unrelated to PH, but a CC over .5 is an indication of other problems.
 

thetekgeek

Bronze Supporter
Jun 8, 2018
255
Nebraska
I just looked through your logs. July 13 through July 19, your FC tests were all below the minimum FC for CYA 50. I suspect you need to bring your FC up to SLAM level for a few days until that CC number drops back to .5 or less.

I also wouldn't worry much about your PH. Your TA is 120 on the last test I see which is probably pushing PH up slightly. I'd let it rise to 7.8 and then add enough acid to drop to 7.4 or 7.5. You may be adding acid a little more often, but over time the TA will naturally lower and the rate of rise will slow.
 

thetekgeek

Bronze Supporter
Jun 8, 2018
255
Nebraska
PH 7.8 is perfectly fine. Let it get to 8 and then drop to 7.6 or so. If you wanted to fight the TA down to 60 or so, you certainly can. Target 7.2 and then aerate to get it up to 7.8, rinse/repeat until TA is down to 60. I don't see much reason to do that right now though because I think you have a possible bigger problem brewing with the CC testing too high and a history in your logs of FC dropping below the minimum.
 

Tuckerclan

Well-known member
Sep 7, 2018
99
Kansas
What do you mean the FC dropping below minimum? How do you add Chlorine? I check everyday, add what it tells me to add, sometimes a skoosh more. I can't check it every hour and add on the hour. Do you add a lot more than it calls for? Do you keep your FC higher than it says, ie: if you are supposed to be at 7 do you add to 15 and then check and add when it gets to 8 or 9? The CC of mine bounces between .5 and 1 usually.
 

JJ_Tex

Bronze Supporter
Jul 17, 2019
1,647
Prosper, TX (DFW)
There is no harm in going above the target rate especially if you have a lot of people in the pool, a storm forecast, going out of town for a night, etc. That way you can ensure you dont drop below the minimum.

Your target rate is FC of 6-8, minimum of 4. Looking at your logs there were times a few weeks ago where you were under the minimum. With a CC of .5 to 1 I'm guessing you have something brewing (hopefully not). You can do an OCLT to know for sure.
 

Tuckerclan

Well-known member
Sep 7, 2018
99
Kansas
Taken from TFP site " It is possible to detect high levels of CCs temporarily in pool water and the CC level will fluctuate from time-to-time but any prolonged measure of CCs above 1ppm is indicative of a problem with the pool water being tested. " I don't think I have had a prolonged measure of CC above 1ppm.
I have clear water, no algae, so I guess I will just maintain a higher level of Chlorine. The app says I should be at 6 so I'm thinking 10? I would think the app would take some loss into account.
 

thetekgeek

Bronze Supporter
Jun 8, 2018
255
Nebraska
You need to target between 6-8 with a CYA at 50.

I would argue that you do have a prolonged elevated CC. Looking through your logs, I only see one test which shows CC at 0 in the past month. 0.5 is ok, but most of your tests are 1.0 or above. @JJ_Tex is correct, you should bring your FC up to 8 tonight and perform an OCLT. Test when the sun is off of the pool, note that number and then test again in the morning before the sun hits the pool. If you pass the OCLT, simply keep your FC in the target zone at all times and never drop below the minimum. If you do not pass, you will want to perform a SLAM. Since the water is clear already, if you need to do a SLAM it should go pretty quickly. The OCLT tonight would be a quick and easy insurance policy to be sure that nothing is growing in the water and causing elevation of your CC's.
 

DanF

Silver Supporter
Mar 17, 2019
265
Chandler, AZ
Taken from TFP site " It is possible to detect high levels of CCs temporarily in pool water and the CC level will fluctuate from time-to-time but any prolonged measure of CCs above 1ppm is indicative of a problem with the pool water being tested. " I don't think I have had a prolonged measure of CC above 1ppm.
I have clear water, no algae, so I guess I will just maintain a higher level of Chlorine. The app says I should be at 6 so I'm thinking 10? I would think the app would take some loss into account.
I determine what my FC should be based on my CYA level. For me it's 8 ppm. So, I test to determine what ny current FC is and add enough bleach to get to 8. I usually add about 2.5-3 ppm (my daily FC consumption).
 

Tuckerclan

Well-known member
Sep 7, 2018
99
Kansas
I determine what my FC should be based on my CYA level. For me it's 8 ppm. So, I test to determine what ny current FC is and add enough bleach to get to 8. I usually add about 2.5-3 ppm (my daily FC consumption).
So doesn't that mean you are falling below your level by morning? Would that mean your morning reading is 5, so you add to get back up to 8?
 

Chasarms

Silver Supporter
May 8, 2020
347
Dardenne Prairie, MO
I don't know about KC, but it has been cloudy and rainy here in St. Louis over the last week or so. When it is rainy and cloudy, my CC numbers tend to be higher. I don't know if it is contaminants in the rain or lack of UV to break down the CC, or a combination of both, but it seems to be pretty consistent under those conditions.

As long as they stay below around one or less and don't seem to be trending up over time, I don't worry about about it. 2-3 dry, sunny days and it will be back down at or near zero.
 

BowserB

Silver Supporter
Jul 29, 2018
344
Katy, Texas
Tucker didn't say it dropped from 8 to 5 overnight. That would indicate a problem--algae for example. He meant from one day to the next it drops. The sun does that, as even when it's overcast, you have UV.
 

DorsalSpine

Gold Supporter
Silver Supporter
Jul 8, 2013
706
Columbus, Ohio
For my CYA, my target is 5 -7, the minimum is 3. Never go below 3! in this case. If my cover is off I may loose 2ppm due to the sun and swimmers. I hold my FC at 7 knowing that the sun will not drive it out of my target range ( 7 - 2ppm = 5). It also gives me a cushion to not drop below the minimum.

If my CC goes above 1 consistently, I do the OCLT. Since it is at night the only loss of FC would be algae. If I pass I just hold the FC closer to 7 and assume the CC was due to test error, swimmer load, pollen, dust or any number of things. If I fail the OCLT, it is SLAM time.
 

PoolNewb2020

Well-known member
May 7, 2020
300
Lathrop, CA
So doesn't that mean you are falling below your level by morning? Would that mean your morning reading is 5, so you add to get back up to 8?
In a healthy pool no. If the FC level is brought up to 8 ppm in the evening, it should still be 8 in the morning. If you experience FC loss greater than 1 ppm through the night, you have to SLAM your pool.
 

Tuckerclan

Well-known member
Sep 7, 2018
99
Kansas
I check my pool in the morning, after a full day in the sun and overnight. I know people on here use more than 1ppm of chlorine a day. Some people are losing 10 ppm a day I lose about 2 to 3. If I have a reading of 5 in the morning the app says I should have 6 with my CYA level. It says add 21oz or 2cups 5 ozs of 12% to bring it up to 6. I usually change the target to 7 and add the 43oz in now calls for. The next morning it will be between 4.5 and 6.5 so I again will do my change to 7 and add accordingly. I do not think this is the wrong way to be doing this.
 

Tuckerclan

Well-known member
Sep 7, 2018
99
Kansas
Tucker didn't say it dropped from 8 to 5 overnight. That would indicate a problem--algae for example. He meant from one day to the next it drops. The sun does that, as even when it's overcast, you have UV.
Thank you. I don't know why this is so hard to understand. All I ever hear on here is slam, slam, slam. I've done that, doesn't change anything, because I don't have an algae problem. It's like when I got my first 286 computer (dating myself). When you had a problem, ANY problem, tech would tell you to reformat your hard drive.
 

PoolNewb2020

Well-known member
May 7, 2020
300
Lathrop, CA
Well, you were not exactly specific about your FC loss. 2-3 ppm FC loss over a 24 hour period is perfectly fine.

Pool Math suggestion is a bit risky IMO, but fortunately it also show the range for a given CYA level. So for 50 ppm CYA it will show 4-8ppm chlorine.
Personally, and I also see a lot of senior members doing this, is to add to the maximum level instead of the suggested level. This way there is a lot more safety margin before minimum levels are reached.
 

Tuckerclan

Well-known member
Sep 7, 2018
99
Kansas
I agree. But people keep saying I am below my safe level at 5 when my level as per the app is 6. A couple of days it dropped to 2 but I added in the morning and the next day it was at 5 again. The question I asked originally was the "cause" of a rising PH or TA and CC rising? I don't have algae, my pool is always clear, after the pollen season I stopped using so much chlorine.
 

Tuckerclan

Well-known member
Sep 7, 2018
99
Kansas
I don't know about KC, but it has been cloudy and rainy here in St. Louis over the last week or so. When it is rainy and cloudy, my CC numbers tend to be higher. I don't know if it is contaminants in the rain or lack of UV to break down the CC, or a combination of both, but it seems to be pretty consistent under those conditions.

As long as they stay below around one or less and don't seem to be trending up over time, I don't worry about about it. 2-3 dry, sunny days and it will be back down at or near zero.
Yes we have had a lot of rain here too. That IS when the CC went up to 1 and then 1.5. Bet you tomorrow it's back down to 1.