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Need help with acid copper bath maintenance / recovery

I use simple acid copper bath of about 2000 lit. I plate products most of the time. I have to do removal of about 250 lits every third day. I have to add acids to compensate.
How can I reduce my removal? Why should excess Copper dissolve in solution? Is my efficiency too low? I use say 200g/l CuSO4, 60 g/l H2SO4 and 28 degree C for plating. Can H2SO4 be separated from the solution removed and used for addition? How?

Kaushik Magiawala
plating shop employee - Gandhinagar, India
2007

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It appears your numbers on copper sulphate ⇦this on eBay or Amazon [affil links] and sulfuric acid are out of whack. A general rule of thumb is 60-90 g/l copper sulphate, 150-255 g/l sulfuric acid, and around 50 ppm chloride. You did not mention plating times / thickness, rack, barrel, or reel to reel? Check your chloride level, it may be too high. Also make sure your anode to cathode ratio is 2:1 minimum. Turn off air agitation and remove anodes if tank is to be idle for extended periods. Remember low current density dummy plating when you start the tank up. What does your copper bath supplier say? A good supplier is an excellent source of information and should be willing to help you. Good Luck!

Mark Baker
Process Engineer - Syracuse, New York
2007