Check out these orchid articles for information and photos.
The first one is about removing Brassavola cuculatta from flask and putting them into compots. Compotting Brassavola cuculatta
The second one is for deflasking Paph orchids, but gives you an idea on size and seedling medium.
deflasking paph orchids
The third article is on cattleyas ( cattleya ), but deals with moving them from the community pot into individual containers. cattleya compot to individual pots
Hope this information helps!