Hello All,
2 part question here-the first part may or may not be an issue depending on if I am understanding it correctly or not. The 2nd part has to be a problem with the app.
At the suggestion of this forum, I have been using (loving) the pool math app this year. Been great to know what to add to get my levels (mostly FC) where I want it to go.
Since I am using liquid chlorine this year instead of the trichlor pucks, I also need to check up on CYA to see if it needs to be added. I was just a touch below the 30 line, so I called it 30 and added enough to get +10 (assuming that would have me just under 40-yeah I know logarithmic not linear and all that)
EDIT-10,000 gal pool
Ok, on to the concerns:
1) I tested my FC and it was 2.5. I wanted to get to to 5.5. So i go to pool math app and using 12.5% bleach it says to add 1 cup 7oz. But then I realized that I still had the 30 listed under CYA so I changed it to 40 assuming that would only change the recommended FC level. Instead, it also changed how much I have to add to 3 cups 2oz. Now I know that the higher your CYA level, the more FC you need for it to be effective. But this is also telling me that the more CYA I have in the pool, the more bleach I have to add to get to the same exact FC level? (read adding 3ppm at 30 CYA needed 1cup 7 oz, but adding the same 3ppm at 40CYA needed 3cups 2oz.) Is this correct or a glitch? I only noticed it because i saw the result and then changed the CYA i have in the pool and saw the result changed. I didn't think a higher CYA made you add more bleach to get to the same desired level, only that your desired level should be higher.
2) Depending on what value in the app you change last, it recommends a different amount of bleach. Let me explain step by step what I did, stick with me:
I click on the FC box in pool math. It listed my CYA as 40. My current FC is 2.5. Lastly, I change the target chlorine to 5.5 and it says I need to add 3 cups 7oz of 12.5% bleach.
Then I change my CYA level to 30 and click "done", then change it right back to 40 and click "done" (and do not change the FC numbers at all). It should go right back to 3 cups 7oz right? Nope, it says I need to add 3 cups 2oz instead.
So what I am saying is that the ending values I had listed in the app were 40CYA/2.5FC/5.5 target FC both times. But depending on if the last thing I changed was the CYA value or the target FC value, the amount of bleach I needed to add was different. That cannot be right! I have not tried this with any other levels like ph or TA yet
So the second part has to be a glitch and makes me wonder which answer to trust.
The first part may or may not be based on if a knowledgeable person says "Yes, you need to add more bleach to get to the same desired FC level with higher CYA". Just to clarify that last point again, I know you need a higher desired level of FC with higher CYA. But the app is also telling me I need to add more bleach to get to the same exact FC level based on what the CYA is.
2 part question here-the first part may or may not be an issue depending on if I am understanding it correctly or not. The 2nd part has to be a problem with the app.
At the suggestion of this forum, I have been using (loving) the pool math app this year. Been great to know what to add to get my levels (mostly FC) where I want it to go.
Since I am using liquid chlorine this year instead of the trichlor pucks, I also need to check up on CYA to see if it needs to be added. I was just a touch below the 30 line, so I called it 30 and added enough to get +10 (assuming that would have me just under 40-yeah I know logarithmic not linear and all that)
EDIT-10,000 gal pool
Ok, on to the concerns:
1) I tested my FC and it was 2.5. I wanted to get to to 5.5. So i go to pool math app and using 12.5% bleach it says to add 1 cup 7oz. But then I realized that I still had the 30 listed under CYA so I changed it to 40 assuming that would only change the recommended FC level. Instead, it also changed how much I have to add to 3 cups 2oz. Now I know that the higher your CYA level, the more FC you need for it to be effective. But this is also telling me that the more CYA I have in the pool, the more bleach I have to add to get to the same exact FC level? (read adding 3ppm at 30 CYA needed 1cup 7 oz, but adding the same 3ppm at 40CYA needed 3cups 2oz.) Is this correct or a glitch? I only noticed it because i saw the result and then changed the CYA i have in the pool and saw the result changed. I didn't think a higher CYA made you add more bleach to get to the same desired level, only that your desired level should be higher.
2) Depending on what value in the app you change last, it recommends a different amount of bleach. Let me explain step by step what I did, stick with me:
I click on the FC box in pool math. It listed my CYA as 40. My current FC is 2.5. Lastly, I change the target chlorine to 5.5 and it says I need to add 3 cups 7oz of 12.5% bleach.
Then I change my CYA level to 30 and click "done", then change it right back to 40 and click "done" (and do not change the FC numbers at all). It should go right back to 3 cups 7oz right? Nope, it says I need to add 3 cups 2oz instead.
So what I am saying is that the ending values I had listed in the app were 40CYA/2.5FC/5.5 target FC both times. But depending on if the last thing I changed was the CYA value or the target FC value, the amount of bleach I needed to add was different. That cannot be right! I have not tried this with any other levels like ph or TA yet
So the second part has to be a glitch and makes me wonder which answer to trust.
The first part may or may not be based on if a knowledgeable person says "Yes, you need to add more bleach to get to the same desired FC level with higher CYA". Just to clarify that last point again, I know you need a higher desired level of FC with higher CYA. But the app is also telling me I need to add more bleach to get to the same exact FC level based on what the CYA is.
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