Thermostat Question!?!

I Have A Heavy Duty Reptile Thermostat and was thinking i could use this connected too my aircooled fan to turn on when tent gets up too a certain degree so its not running constantly and hopefully it will keep my 3x3 warm since i am in ne us and the room temp is about 50f day and night with windows open. anyone run a thermostat in there tent? how do you set it up?

You can solve the problem without doing it that way. First, when your lights are off, the ambient temp should be within range, so you don't need the fan running then, at least for temperature reasons. When your lights are on and you need air flow, simply use a dimmer switch to adjust the fan speed to maintain a consistent temp.