Humidity $@^#!~*

Ok i got a good handle on the humidity when the lights are on, i just flick on the exhaust fan and its down to about 35-45%. I dont have the inline fan hooked up to get the air in i just open up a vent on the bottom of the tent. The inline fan makes the temp drop to about 50-60 degrees at night. My light go on at 8am so when i get up i check the humidity and its up to 90%. I am going to get a mini dehumidifier in about a week. Is there anything i can do to decrease nighttime humidity. I cant leave the vent open so i cut of the exhaust at night.

is there any way to get that dark temp up,like say to 66-68?Thats way cold for the plants,and what happens is when you spark that lamp,the dew collected from the very cold temps are evaporating,causing a fluctuation in the humidity.

The cooler the temp. the higher your relative humidity will be with all other things being equal.
Cold air holds less moisture than warm air can.

While others are tryna figure out how to bring down temps i gotta bring it up! I have an extra duct fan so i think i will have to buy another thermostat to make it blow hot air and i will use that at night only and that way i can run the exhaust.