Me personally I don't like dark tubs that are always closed up,I think it's cruel and unfair. So don't See why anyone would want there animal to live in darkness...even though they are in hide 90% of the time..I feed my snakes right in there enclosure and I have them in tanks.. So ,no, covering the top dark is not necessary. They don't kill in there hide,just while he is eating leave him be,don't try petting him or picking him up,just leave him be. Try not to over analyze every situation. Just keep it warm and humid and comfortable and hive him a place to hide and you will be fine. As complicated as people make it sound around here at times when it comes to husbandry,I have my first 2 snakes for three months now and I have evrything running basically perfect. Took a while of messing with diff watt bulbs,placing the heat domes etc...but once u find that spot,stick with it