I've been told that chlorine bleach will kill the moss (and other
green stuff?) that is slowly eating my cedar fence rails, and very
very slowly my fence posts. Only the ones that don't get much sun.

But where do I get chlorine bleach? Even CLORox has only sodium
hyposulfite. And this isn't the Ultra, which I think is meant to be
color safe.

Although there is no H in Clorox.

When did it happen that they took the chlorine out of regular bleach?

This is what the Clorox site said:
Chlorine and liquid bleach are one in the same.

Actually they aren't. The term "chlorine bleach" is actually a misnomer. What's in the bottle is sodium hypochlorite, the active ingredient in liquid bleach. Although chlorine is used to manufacture sodium hypochlorite, there is no free chlorine in bleach.

But on another page it refers to sodium hypochlorite killing fungus.

Meirman

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