I thought that this might need to go in the caging forum, so sorry if its meant to be there and not here.

My question is, how fast should I be losing humidity in my tubs? How much ventilation do I need?

I've just finished my 4 tub rack, and I've been testing my heat and humidity. Heat is fine, with high 80's ambient, and low-mid 90's on the hot side. So thats all good as far as I can tell, but I tested my humidty by spraying the tub down and getting a base and seeing how it holds. Well, I sprayed too much and humidity jumped to 80%, I did that around 1am PST, when I checked it this morning at 9am PST, it was at 78%. I've been checking it with a digital thermometer/hydrometer.

I'm thinking I need more ventilation? The tub currently only has 6 holes.