Hi Nicki. Phrags are not as difficult as Paphs. You have to make sure that the water you give the plant is very fresh , by this I mean you can water it every day from the top,which ensures that there is no build up of 'nasties', and which will provide the plant with the oxygen it will need. Regarding compost I use sphagnum moss mixed with large perlite but if you follow the watering plan you could use anything--bark mixes, sphag and charcoal,in fact. I have been successful with a kovachi hybrid grown in nothing but granite chippings. Just keep it well watered and it should be no problem.
Good luck
Ed