I have grown Grandiose x ramosa in the past. Mine had been newly taken out of flask and I put them in small chips of red lava rock and eggshells, basket pot. I watered with distilled water daily and rarely used fertilizer. Water was always in the saucer. The area in which they grew had many other plants so they had good humidity. They received very bright shade. They did very well this way. In April, I bought a rootless Aeranthes grandiflora so I have been keeping it in a tank with the Bulbophyllum until it has a good root system. It seems happy there for now but eventually, it will need more light....
Here is some good information about Aeranthes.....
Angraecums...: Aeranthes Grandiose