Hello, can someone offer me some advice - I was using the Copy Cadinum and Zinc kit on some steel brackets, they were all glass beaded, lightly polished, cleaned, and the first few plated pretty nice, bright shiny plating,,,, then the last piece (prepared the same) simply turned grey along with the anode? what an I doing wrong? the current and voltage settings on my power supply were the same, pieces are the same size, do I need to clean the anode? do the anode get used up this fast? when do I know when they are no longer good? Please advise...