Check cynthia's thread of the skewer method -
http://www.orchidgeeks.com/forum/new...=skewer+method
This potting mixture should work - but it definately will take more monitoring to make sure you don't over water. People often get away with watering on a routine schedule with bark - say once a week. With coir mix it will vary depending upon the time of year - could be as long as 3-4 weeks depending upon your conditions.