I just purchased the Chalet Cherrywood Humidor (25-50ct). I am in the process of seasoning it with a little dish of distilled water in it. It cam with a hydrometer with velcro to attach. I noticed on the back of the hydrometer had 4 holes. I attached the velcro which pretty much covered them. Do these holes need to be open to read the humidity? Can and do I need to calibrate it? It also has a light plactic band around it, should I remove it? I have velcrowed and stuck it on the inside of top cover of humidor.