Hey guys! I actually have a few questions, however my main question has to do with fertilizer. I only have 6 active orchids, all phals (two are in sphag and bag mode at the moment) so I don't have a giant, gallon-sized container for watering or anything, as I dunk my orchids once every 7-10 days when they're dry for a nice drink.

Because of this, I only have a spray bottle in which I keep my water-soluble fertilizer. I made up a batch a few weeks ago and I am wondering if it breaks down in the water the longer it sits? Like if I spray it in a week or two from now, will it have all broken down and I might as well not even bother? Do I have to mix up new fertilizer often? I fertilize them when I water them, so probably "weakly weekly" as it were.
Another question I have is that I'd like to start looking into other kinds of orchids, not just the standard phals that I've got here. That said, I am looking for something that requires about the same, if not slightly more (not by much though) light as phals? Any suggestions?
Finally, my fiance is on this aeroponics kick (he wants to be able to grow fruits and veggies inside at our new apartment and we won't have a balcony/patio) and he really, really wants to see if orchids can grow that way. I was wondering if anyone knows whether or not people even do that, or whether it would work? And if not, would anyone be interested in following the progress of his science experiment? I won't let him have any of my plants, I'm just going to take him to a Lowes clearance rack or something to pick out his own so if he kills them they aren't mine, hehe. But I thought I'd at least throw the idea out there in case anyone was curious/knew anything about it.
Thanks!