Care for orchids in charcoal

[Nicolasdperez]

Hello, I recently potted a few of my orchids in charcoal and was wondering if anyone with more experience has advice for care in charcoal. I have done some research and this is what I know so far:

1) charcoal is very porous and will absorb salts. Hence salt based fertilizers should be avoided to prevent salt burn.
1) charcoal should be natural as many bbq charcoals have added chemicals to help with combustibility.

What I am unsure about:

1) does charcoal need to be flushed and if so how often?
2) can the ph of charcoal negatively affect orchids?
3) what are good organic fertilizers to use in charcoal?

I love how accessible and cheap charcoal is so it would be great if someone could help me navigate the intricacies. Thank you for your time