[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: Flourish Iron - rusty?

>I've been reading these posts about iron being bioactive, and now I am
>worried about the bottles of Floursih Iron I have. When I open them they are
>a clear yellow, but over time they darken & become somewhat more opaque (or
>maybe it just seems that way because of the darker color). Is this color
>change an indication that the iron has gone bad?
>- -Rachel

The darkening in color is normal and is not an indicator the iron 
going "bad". The change in color is a result of mild oxidation of the 
reducing agents we use in Flourish Iron (to keep the iron reduced). 
Every time you open the bottle you let in a little oxygen which 
results in some oxidation. Think of it like a buffer, the reducing 
agents are the species getting oxidized keeping the iron "safe" in 
the ferrous state. There is more than enough of the reducing agents 
to prevent ever getting a precipitative loss of ferric iron in the 

Also, if the bottle is stored in a warm or hot environment there may 
also be some darkening due to a process referred to as "Maillard 
reaction" (also known as food "browning" chemistry). But again this 
is just a change in color and not an indicator of loss of quality or 

Gregory Morin, Ph.D.  ~~~~~~~Research Director~~~~~~~~~~~~~~
Seachem Laboratories, Inc.      www.seachem.com     888-SEACHEM