Ok, so I am salt testing one of my new hygrometers and I have a few questions.

1) How long do I let the hygrometer sit in the baggie before I get a good reading? I read both 12 and 6 hours.

2) I also want to salt test my other hygrometers. Do I have to make a whole new salt water bottle cap or can I just take the first hygrometer out of the baggie and put a new hygrometer in and wait the proper amount of time suggested above?

Thanks for the help.