Will a copper BB work?

Always start at the top and work down, since when you rinse, that is the way the solution will go.

There is no real way to get a 'copper' color, but a bronze/brown is 20 volts.

The driver would be USB powered, not WiFi.

It should work for any sim.

Copper turns a bluish-green color (called patina) when in salt water. This is due to saltwater corrosion.

Copper sheets previously used in solar cells can be melted down and stripped of impurities, to form high-grade copper as a product, but this would require lab equipment.

Mix 3-parts baking soda with 1-part vinegar to make a thick paste. Use a microfiber cloth to scoop the paste up and rub it into the copper. Then, rinse it...

You should try soaking it in lemon juice as the acid can remove copper rust.

Acid neutralizer added to your water system. I have also added a water softener to my system.