Re: Ferric Citrate

> From: Adrian Hydon <aph at globalserve_net>
> Date: Tue, 28 Jan 1997 17:20:32 -0500
> Subject: Ferric Citrate (Iron III Citrate)
> Is Ferric Citrate an acceptable source of iron for a plant?  The iron is
> in the III oxidation state.  Does it need to be Fe II or Fe III???  What
> about the citrate?  Will it affect the plants? fish?  The amount present
> will be very small, and I know that Sodium Citrate is not toxic in small
> doses to humans (It's used as an anticoagulant by the red cross).
> Any feedback is welcome.  I am really looking for an iron source that I
> could obtain from a chemists.

I have been using ferric citrate as a source of iron for my 29 gal planted
aquarium for about a year.  It seems to be well utilized by Water sprite,
Cryptocorynes, Lysimachia and numerous algae.  As far as I can tell, it has not
adversely affected the Platies, Rams, Otocinclus or zebra danio, except
possibly, if I overdose, some of the platies show a whitening around the
mouth, which I suspect might be a fungus.

The reddish-brown powder (borrowed from the lab) dissolves very slowly at room
temperature, but
more rapidly in hot water.  I keep the stock solution in the refrigerator (the
compound remains in solution) and add a few drops every few days.

Citrate is a chemical compound found in most cells and is important for its
role in the metabolism of carbohydrates and fats.

-- Curtis Hoganson
Dept. of Chemistry, Michigan State University
East Lansing, MI 48824   517-355-9715 ext 260