Corrosion between Copper and Stainless Steel

[Tater Patch Kid]

I can't say i have read about any corrosion forming on any of your stills.
Just wondering if it is forming inside your condenser or apearing on the outside? I know it must be forming because it forms on water heater plumbing. Reference; beer keg stills or even stock pot setups. Maybe cause your stills are not in use all of the time. Comments Please, Just Wondering???