i have a hog island boa in a cage with a metal top. i mist all the time and can NOT FOR THE LIFE OF ME get the humidity right! i have a humidity hide, damnp towel on top of the cage, moss, waterbowl under the light...... UGH!! im thinkinkg of getting a humidifier,......do they work, and what is a good one? can i get one that will sense when the humidity gets too low and it will turn on?