I have my diluted fertilizer in a spray bottle. In addition to bi weekly drench fertilizing, I spray fertilizer water on the base of the orchids every other day. Not enough water to rot roots or wet the pot but enugh for it to be taken up by some parts of orchid roots.

Why so much fertilizer? Unless it is VERY dilute (like maybe 1/8 strength) you're overdoing it.
And if you're just dampening the surface (so that the water evaporates quickly) the solids will, over time, become more concentrated. I hope you are flushing well with clear water (no fertilizer) every couple of weeks, that will mitigate the salt buldup.