Terrible time checking PH this year

[waterbear]

Evan probably nailed it. With the PS-233, you need R0014. With the PS-232, I think Ben used R-0004. They ARE different in concentration, and I believe R-0014 has chlorine neutralizer as well. (I don't think 0004 does.)

R-0004 is also stabilzied against high clorine levels but is meant to be used with a 45 ml water sample so acid and base demand tests can be run (useless tests except under very special circumstances that most people will never need).