Testing high chlorine levels

pcmacd

Well-known member
Oct 3, 2010
68
Mesa, AZ
#1
Using the TF-100 kit w/ R-870/R-871 components. I balanced the pH and shocked the living daylights out of the pool with liquid chlorine. Went to test FC. Put scoop of R870 into 10ml water with speedstir, turns clear right away. A second scoop it stays pink. Then 70 drops of R871 tells me I am at the correct shock level for CYA of 90. Am I doing this correctly?
 

ajw22

Gold Supporter
TFP Guide
Jul 21, 2013
3,216
Northern NJ
#3
You need to MAINTAIN a FC level of 35 or more with a CYA of 90 for the SLAM process. I would add a bit more CL and have it above 35 when tested so it never drops below 35 as the CL is consumed killing the algae.

The more you maintain the FC above SLAM level the faster it will complete.

Brush the entire pool a few times a day to break up the algae biofilm and allow the chlorine to attack the algae.
 

Texas Splash

Mod Squad
TFP Expert
LifeTime Supporter
#4
Then 70 drops of R871 tells me I am at the correct shock level for CYA of 90. Am I doing this correctly?
Just a thought if you care to try it …. but with such a high CYA and equally high FC SLAM level (70), you will go through drops like crazy. You might consider using a 5 ml sample so that each drop equals one FC. Basically, 35 drops equals an FC of 35. A water sample of 5 ml is not as accurate as the 10 ml, but at that elevation it's all hand grenades anyways - it's not pinpoint accuracy. So in the early part of the SLAM that technique might help for a while and save you some reagent. As you near the end of the SLAM and/or the OCLT test, then go back to the 10 ml sample for accuracy. Something to consider.