Talking about fertilizers is like arguing about what is the best motor oil. I wonder why not use a fertilizer that has been around for decades? Good old 10-15-10 7 drops Schultz. Any opinions dear friends?
I believe Schultz contains urea, which is a form of nitrogen that is not usable by orchids without first being broken down by microbes in the mix. Because orchid mix is soil-less, there are very few of these microbes to do the job. I wouldn't use it and find the urea-free fertilizers very easy to come by.