humidity question
 

If I can keep my orchids in 75% humidity sould i not water all that much?

Depends on the orchid and the time of year. In my yard it's very humid in the summer, more than 75% for sure. During that time I water my vandas 2 times a day. Right now it's probably down to about 25% but it's not as hot and the sun stays lower on the horizon. I water once a day now and if I skip a day I won't even worry.

I have a small orchidarium it goes from 60-75 degrees and has a fan and 14 hours of light.

In that environment you probably it would seem to me that you shouldn't have to water as much with the higher humidity. Still I have no experience with terrarium growing. If you haven't looked yet, here's a good place to start.
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