My partner and I recently rescued a couple of Phalaenopsis plants from our local Lowes home improvement store. They were $4.99 each, and aside from having no blooms, they seemed to be viable plants. The leaves looked green and healthy, and the only reason they seemed to be on the discount rack was because they didn't have any blooms (I guess no one wants to buy an orchid without seeing what the bloom looks like). So we bought a good quality bark potting mix. We water them about once every 5 days or so, by soaking them in water for 15 minutes or so. We've used a general purpose water soluble fertilizer at half strength about every other watering. We also mist them almost daily. They are in a medium light setting (they don't get any direct sunlight, but they get quite a bit of indirect sunlight). Here's the problem. They started to show buds (about 3 or 4 each), so we were excited. They grew and grew, and just as it seemed like one or two were about to open, they started turning yellow, then within a few days, they fell off. :( Now even the younger ones are starting to turn yellow. Any ideas? What did we do wrong, and what do we need to do?