Calling all Geeks

[chem geek]

I agree that "organics" is a decent catch-all phrase for the stuff that gets into the pool that chlorine deals with. Technically, though, ammonia is not organic as it does not contain carbon (carbon dioxide is usually considered inorganic even though it contains carbon -- yes, it's confusing) and yet chlorine certainly gets consumed by it. It seems to be the only inorganic compound that is normally introduced into the pool and eats up chlorine (the resulting chloramines are also inorganic and eat up more chlorine). Sodium Thiosulfate that is used to eat up chlorine in the alkalinity drop test (or to remove chlorine from pools -- rarely done) is also inorganic, but is not normally found in pools.

The ozone produced in ozone systems can also use up chlorine (and vice versa) and ozone is also inorganic, but hardly anyone on this forum uses an ozone system.

So this is why I usually say that chlorine gets used up by "ammonia and organics" -- just because I'm an anal-retentive chemistry geek.

Richard