It's a good lookin rack. 70 % humidity with four big females on a row, could cause sagging. a 4000 gram snake is around 10 pounds plus water bowl. breeding season you will have males in with them. a thin support in the middle makes a huge difference. I understand putting in snake room and I think temps will be ok. what ever size heat tape you use, make sure you use one of the high end thermostats. good luck don