Zygopetalums on the whole seem to like quite a lot of water (but not to be soaking wet all the time) - which means only watering every two weeks might not be enough?
I actually grow the remains of mine in S/H with good success. I put the old bulb that was all I had left in a S/H pot and several years later I have 3 growths which are getting bigger with each successive one. It loves the wet when there is plenty of air, I'm just careful about water on the plant.
I actually grow the remains of mine in S/H with good success.
Mine has been sulking in LECA with a puddle of water at the bottom of the pot (semi-semi/hydro!?) , but I think it's starting to come right again. It has a number of new growths, which I'm happy about; its roots were quite sad when it was repotted from bark into LECA, so I imagine that's where the setback occurred.