thanks for your quick, detailed and helpful reply. It is amazing the misinformation one can gather as a brand new orchid Mommy. I will try to weigh the pots, but will have to buy a scale first. It will be complicated because I have 15 orchids in different size pots from 3 different stores. Each store uses different mediums.
Take a look at the sticky thread The Phal abuse ends here. for some general cultural information about Phals. If you can select a medium that works well for your conditions (humidity, temperature, how often you can water) when you repot, you can put all in the same medium which will make your life easier. As far as weighing, you will probably fairly quickly discover a time interval between waterings that works for you.