if u don't have a dehumidifier, someone recently suggested an empty lime bag, in the room.
probably don't require a/c. see if running the a/c, on fan only mode, for 15min (for starters) & see whether it pulls moisture out of the 85% range, for u.
what's your feeding/"watering" ritual?
I'm in aero, but i have a cursory knowledge of soil. it's been a long time & i knew nothing, when i ran soil. i come across a lil of this and a lil of that, though so...
however, i would stip that whatever a soil (if that's your medium- i see the vermiculite) grower has to say... I'd listen to them, over anything u get outta me. it's likely, they'll want all that intel. also- ummm... diox... ppm, if any?
u have the beginning, of clawing, if they aren't shrugging, over a moisture issue. might look that up, as well. RH, ph, distance to what lighting, and soil ppm/"hotness" ;D , is where i would begin.
don't let that keep u from gettin those other figures.
oh and tap, or r.o.?