Pitting Problem in Wood's Nickel Strike

Hi I am a metal finisher out of Houston Texas. We do decorative plating on a variety of different base metals. We generally put acid copper over the parts then buff the parts. Then we generally put sulfamate bright nickel then to gold. My problem lies with my nickel strike tank. If a part is cut through to the base nickel plate or if it is made of stainless we nickel strike the part.

Lately we have been getting pits when we go through the nickel strike. I've dummied the tank and I feel that the copper has been drawn out of the bath so I have ruled out that problem. I've also been carbon treating the tank to pull out any organics. Nothing is seeming to work - Is there anyone out there who has experienced the same problem ? Please help!

My guess is iron contamination. A little iron goes a very long way as ferric chloride ⇦ on eBay or Amazon [affil link] /HCl etchant. I would do a lab test before and after a lab treatment with peroxide or permanganate (high pH) treatment to see if that is your problem.

Carbon does not pull out all organics. Frequently a peroxide treatment is necessary to make it amenable for carbon treatment.