Nice link John. That puts some credibility behind the proportions for chlorine treatment. I think that proportion table is for chlorine that would be residual in the potable water (to be consumed by people & pets). If you are "sanitizing," and would be draining & refilling, you could use higher concentrations up to a reasonable level, as the higher concentration will only reside in the tank & piping for a short time, then will be diluted by draining & refilling.
Baja-tested '08 2-slide 36'
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