I recently acquired a juvenile basilisk, and have had no trouble with environment or nutrition thus far except in the department of humidity. He is in a 20 gallon (long) terrarium and is about 5 inches from snout to vent. I mist twice daily, but I am not always home, and am concerned about the fluctuations from 90% right after misting to a stable 45-55%. I need to consider automatic options for providing the requisite 70-80% humidity gradient. I have had some limited experience with the ionic foggers- they create an instant stable 100% humidity.

My question is this: How much is too much? will this amount of humidity create long-term problems (breeding fungi, bacteria etc) and can this be circumvented by regular vigorous cleaning? Is the 45-55% humidity most of the time a problem in the first place or am i worrying about nothing?

Most importantly: is there an automatic method available that is practical for his juvenile setup and that can maintain the ideal 70-80%?

Thanks for all responses.