Q.Large copper container
I am planning to use a copper container for marginals/water plants and have a fountain
and oxygenator with perhaps some small fish.
I would think I need to paint the inside of the container.
If so what would you recommend?
Copper makes a fabulous medium to work with, due to its rust resistance and the patina it develops. Avoid copper if you want to raise fish. Copper containers and copper fountain units leach copper into the water, which can reach levels toxic to fish.