I purchased a used spa and I am currently trying to get the water balanced and the correct amount of sanitizer. So I have been doing a on of research on the internet (thanks chemgeek, waterwizard, nitro etc), but I am confused about some of the Free Chlorine numbers.
So my first question is Dichlor says 4-5 ppm, yet they say reentry is prohibited unless its below 3ppm....why? I don't understand this...
Most test strips and manufactures recommend 3-5 ppm for a spa. But they don't say at what CYA levels. From my understanding with 0 CYA, wouldn't this be a very harsh amount of chlorine and be hard on the equipment, swim suits etc?
For instance I bought a Chlormaker DO, they state maintain 4-5ppm. They say nothing about CYA.
Should I add 30 ppm CYA like some advise and do I need to up the free chlorine levels higher then 4-5 ppm in order to compensate for the reduced chlorine effectiveness?