Use this instead of soil, you’ve never had orchids like this: they will be very bushy

The appearance is very similar to that of polystyrene balls, in fact,  perlite is white  and very light, it does not even alter the  pH of the orchid  . Nurseries use it to promote the growth and development of the plant, because it allows correct reception of water and facilitates the respiration of the roots, since it is not compacted like soil and therefore it is impossible for water to stagnate.