how much chlorine ppm should I looe each day??

[armom]

My pool is crystal clear and I am super happy about that. But I am trying to figure out if I will need to increase my CYA level to be able to hold chlorine. A few days ago I passed all three steps for a SLAM. I have had no CC every time I test my chlorine level. Here are my current numbers.

PH- 7.8
TA - 120
CH- 225
CYA somewhere near 40, but was in between 30 and 40.
FC - 5
CC - 0

My pool is direct sunlight all day. We have no trees on our property in back yard. We live at 1300 ft above sea level ( I don't know if that makes a diffence, but I thought I would throw that in).

My pool has been losing a large number of chlorine daily. Example : Yesterday my FC was 2.5 and I added 128 oz of 10% chlorine. My FC reading 24 hours later was 4. I did have a few swimmers yesterday and temps of high 90's. Please give me thoughts as I am new to the BBB method.

 

[Defgufman]

We don't practice the BBB method, we use the TFP method
During peak sun with people all up in the pool I lose 2 to 4 ppm fc a day. On less sunny days I drop 1 to 2 ppm fc.... You need to decide where you want your cya....I like mine between 50 and 70. What we want is control over our chemicals in our pool as opposed to begging the pool store gods for mysterious answers.

 

[Yev]

So you added 7.5ppm FC, so your FC level shoudl have gotten up to 10ppm. So you lost 6ppm of FC. Here is my first question. What time of day did you add the FC? If you added is lets say at 3pm, then you lost some in the sun on day 1 and some in teh sun on day 2. In that case, 6ppm with 2 sun sessions and a swimmer session seems possible. If you added that at lets say 9pm, then 1 day of sun and 1 swimming session seems like a lot.

A lot of people forget that the CYA scale is logarithmic. So if it is half way between 30 and 40, that is not 35, that is more like 31 or 32. I would think that if you get all day sun, get your CYA to at least 40, and then keep an eye on it. You can probably go to 50 as well and be OK. Just remember that you have to follow the CYA/FC table to maintain sufficient FC in yrou pool for your CYA level.

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So you added 7.5ppm FC, so your FC level shoudl have gotten up to 10ppm. So you lost 6ppm of FC. Here is my first question. What time of day did you add the FC? If you added is lets say at 3pm, then you lost some in the sun on day 1 and some in teh sun on day 2. In that case, 6ppm with 2 sun sessions and a swimmer session seems possible. If you added that at lets say 9pm, then 1 day of sun and 1 swimming session seems like a lot.

A lot of people forget that the CYA scale is logarithmic. So if it is half way between 30 and 40, that is not 35, that is more like 31 or 32. I would think that if you get all day sun, get your CYA to at least 40, and then keep an eye on it. You can probably go to 50 as well and be OK. Just remember that you have to follow the CYA/FC table to maintain sufficient FC in yrou pool for your CYA level.