1.There's no corrosion or oxidation, the copper is shiny and new.
2. Our mash is cooled with a water jacket.
3. I'll probably upgrade to SS soon, the copper coil was the largest option that was available (plus it was a good price)
There's nothing to indicate that anything is going wrong here, I'm a guy who started a distillery with no prior distilling experience, so I feel I need to be extra cautious. I've consulted some chemists/chemistry nerds and no one seems to think that this is going to be an issue, so I guess it's all clear from here. Better safe than sorry!