Chlorine - testing and safe levels

[Tvaughn6]

We were having a couple of green spots on the bottom of the pool so I am in the process of slamming it. My cya is between 40 and 50 so I’m keeping my FC at 20 (actually a little higher, oops). My two questions are:
1. What FC level is it safe to go swim? I have a 1 and 3 year old.
2. with a cya between 40 and 50, my target level is between 5 and 8. Does this mean I can no longer use my small chlorine/ph test kit and need to always use the one from my large test kit?
Thank you!

 

[Newdude]

Hey T. Swimming is safe up to SLAM levels based on the FC/CYA Levels

The OTO drop/ block FC test is not reliable after 2 ppm so for our purposes it’s basically a test strip and not used. It will tell you that you have chlorine available but how much is sketchy at best. Use the FAS-DPD powder test for reliable results.

Also, the CYA test rounds up to the next 10, so 4* equals 50. as such, it’s easiest to just fill to each 10 line and check it. If you still see the dot, go right to the next 10. You can suck the water back into the squirted and redo the test as many times as you need.

 

[Tvaughn6]

Great tips. Thank you!