I repotted my one remainig orchid with added chipped bark from a pile we ordered for mulch in the garden. I fill the pot with water once a week and let it sit for half an hour then drain it and spray the roots with an orchid food spray.I should point out that before doing this I gave up on 3 others and binned them so this is a lone survivor and I only found the orchid feed spray 2 months ago. It has since put on 3 new leaves and is looking OK. If it hasn't produced a flower spike in 6 months it too will end up in the compost bin. It has been warned.
@Hostafan1 is an expert on orchids, he has loads of them. Maybe he can help you Steve.