Using ferric chloride in etching copper dies

I work at a printing company in GA. I use ferric chloride ⇦ on eBay or Amazon [affil link] to etch copper dies in a spray tank. Well I came into work one morning and my tank had "sludged over" I call it.It was a fresh tank, with fresh chemicals in it. The ferric chloride ⇦ on eBay or Amazon [affil link] had turned from a normal black looking color to a green color and had some sort of film in it.Well I Want to know why it did that.
The chemicals that I use are 13-A and 13-B. The copper content was around .3 on the spectrometer.

PLEASE HELP

It sounds as if you have reduced the ferric chloride ⇦ on eBay or Amazon [affil link] to ferrous chloride, hence the green colour. I would think this has been achieved by something, such as a lump of copper or other metal, being dropped into the ferric chloride ⇦ on eBay or Amazon [affil link] tank, where it has been oxidised by the ferric solution to give a soluble salt of the metal. Run an ICP to see what other metals are in the solution.

respected sir,
I want to etch the surface of copper rod. I started to etch. But I don't know about the effect of concentration of ferric chloride ⇦ on eBay or Amazon [affil link] . Now I am using high concentration. Is high concentration decrease the etching speed?
please check the above question and give me your valuable advice.