When I get the FC reading and add reagent 3 for the CC reading I can not tell any change in the color. I know something is growing in the pool. Why cant I see any change in the CC's? Am I misunderstanding something?
Smykowski said:ChemGeek put together a great post in the deep end that explains this:
Combined chlorine (chloramine, dichloramine, and nitrogen trichloride) primarily results from Free Chlorine (aka hypochlorous acid) oxidizing nitrogen based componds, such as urine/urea) ammonia, sweat, etc. If all you are doing is killing algae and not oxidizing the above, it's very possible you won't ever see CC show up before, during, or after the SLAM process.
Richard320 said:It might be dissipating in sunlight. Are you SLAMming the pool? In which case, worry more about the overnight loss; that will tell you if something's still growing.
scott.MI said:Smykowski said:ChemGeek put together a great post in the deep end that explains this:
Combined chlorine (chloramine, dichloramine, and nitrogen trichloride) primarily results from Free Chlorine (aka hypochlorous acid) oxidizing nitrogen based componds, such as urine/urea) ammonia, sweat, etc. If all you are doing is killing algae and not oxidizing the above, it's very possible you won't ever see CC show up before, during, or after the SLAM process.
How do you know that something is growing in your pool? Do you see algae? Are you losing too much FC overnight?brian10 said:I know something is growing in the pool.
JamesW said:How do you know that something is growing in your pool? Do you see algae? Are you losing too much FC overnight?brian10 said:I know something is growing in the pool.
Has your FC ever dropped below 7.5 % of your CYA?
JamesW said:Black algae can be one of the more difficult algaes (actually, it's a type of bacteria) to deal with. You need to go through the SLAM (shock) process. For black algae, it's important to brush at least once per day.
Once you have cleared the pool of all algae, it's important to maintain a minimum of 7.5 % to 15 % of the CYA at all times. For a CYA of 40 ppm, that's 3 to 6 ppm. That means never below 3 ppm. I would target 6 ppm just to have that margin of safety.