80% RH is fine but if it gets into the high 80s %RH you need to look at dehumidifying.
A wee bit of physical chemistry :
Relationship of water vapour pressure to temperature (of the water)
Relationship of relative humidity to temperature (of the water)
can clearly be seen the warmer the water, the higher the rate of vapourisation (and higher the water vapour pressure) and this has an effect on the relative humidity of the air in the tank. I don't keep water bowls in my beardie's tubs or tanks. The water warmed by the basking light will be pushing up the RH in the tank .
My beardies have always been well
hydrated because they get
hydration from their daily live insects (crickets & silkworms) and the greens when I can get them to eat their greens. My girl is not a fan of the version of choi that's in season here ATM …. so I give it to the crickets (to gut load them) and she get's the gutloaded crickets and is none the wiser.
Bathing wont help with
hydration unless the dragon actually drinks the water while sitting in it.