What levels of Sodium and Chloride are "safe" for orchids??

[Ray]

It is interesting how salt tolerance varies all over the map - cotton is highly tolerant, while corn is less so; it's too bad there are no established levels for orchids, although I would expect it to be low, considering most salt exposure to plants is in the soil, which our "babies" never see in nature.

With the levels you have, I'd highly recommend that you consider an RO system or other way to avoid using your tap water.