Re: NANFA-L-- Precipitate

Jerry Baker (
Wed, 25 Jan 2006 21:52:58 -0800

geoffrey kimber wrote:
> To be honest, I have never measured the ammonia level after removing
> chloramine with thiosulfate. I cannot find the exact chemical formula
> for the chloramine that is used to disinfect tap water, but it is made
> by reacting chlorine (either gas or hypochlorite) with ammonium
> hydroxide. One site stated that munical chloramine was 61% chlorine
> and 39% ammonia, which would not be too far off if the formula was
> NH3Cl

I do believe-in-pH > 7 the monochloramine (NH2Cl) is the dominant
species. There are also NHCl2 and NCl3 species that occur.

> I'm going through this because-in-1ppm of chloramine (a common
> concentration in drinking water) you would end up with .31ppm. 1ppm =
> 1mg/liter, so this could potentially be in the toxic range if you did
> a big water change, depending on pH. besides - even if it's not
> toxic, it just gets converted to nitrate and I have more algae growing
> and I have to change the water sooner.

If you keep live plants you have to add nitrates and phosphates to keep
the algae from growing ;)
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