I have made over 10,000 home made boards in my lifetime and I speak from
experience. The crystal power will keep indefinitely. I have never had a
problem storing the powder. I bought a 5 gallon bucket of A.P. from
Kepro. I took a few plastic containers and filled them for smaller
storage. Some were open, some were tightly sealed. Never had a problem
with any of them. It is the best, cleanest, and safest to use. I used to
use FeCl in earlier days. I will never touch that stuff again. It stains
everything it comes in contact with, splashes are hard to control, it
eats its way theough clothes, and storing and disposal is harder.
Rick
http://www.pic101.com/pcb"Rick C." wrote:
> The crystals unmixed will keep indefinitely.