trader_4 wrote, on Thu, 26 Jun 2014 05:31:48 -0700:

B - I find it hard to believe it's right, because if you look
at the water quality recommendation from pool standards organizations,
public health depts, etc, I've never seen the chart or anything
that says your high levels of chlorine are needed.

Hi trader_4,

I understand what you're saying, so, we need to look at this
closely, scientifically, and logically.

Both you and I can understand the *logic* of the CYA-to-chlorine
argument. It's why pool stores test CYA in the first place.

The higher the CYA, the less effective any one level of chlorine
is. We all know that, so, at least the "inherent" logic is
underlying the charts.

But is it science?

This technical bulletin lists a few scientific references:
http://www.aquaticspecialtyservices....hbulletin1.pdf

Namely, the following which, the bulletin says, conclude:
"cya inhibits chlorine's ability to kill bacteria".
a) American Journal of Public Health, October 1965, Anderson
b) Applied microbiology, May 1967, Fitzgerald

Yet, we are saying most "official" recommendations don't mention
the CYA level, right?

Here's an 'advisory', that says, essentially, the same thing:
http://www.accu-tab.com/Portals/0/pd...A_Advisory.pdf

So, maybe together, we can flesh this out, to understand why most
official chlorine recommendations don't seem to take into account
the CYA levels.

One potential "error" in our assumptions is that an *indoor* pool
probably doesn't have *any* CYA; so, any "official" recommendation
for chlorine levels in an indoor pool wouldn't be pertinent.

Another potential complicating factor is that, for outdoor pools,
the CYA levels might be "assumed". I don't know, as we'd have to
look at each official recommendation to be sure.

This post is getting long, so let me google for "official"
*outdoor* pool chlorine recommendations to see what I can dig
up to support or disprove the hypothesis.