What about Calgon?

[Anscojohn]

The thread about Arm and Hammer Washing Soda caused me to ask the experts. Can super market Calgon be used in hard water, or is some kind of special chemical needed? Thanks in advance.

 

[Photo Engineer]

Calgon changed their formula about 20+ years ago. It is no longer suitable for use in photographic solutions as a sequestering agent. Kodak uses a product called Quadrofos. I've used EDTA and the Dequest series of chemicals with great success.

PE

 

[jim appleyard]

You can pick up EDTA at Artcraft.
http://www.artcraftchemicals.com/products_1.php

 

[Photo Engineer]

Disodium EDTA is probably best to use.

PE

 

[Anscojohn]

Thanks, fellas.

 

[Keith Tapscott.]

The stuff I use is sodium hexametaphosphate, although you could also try sodium tripolyphosphate.