do dubia roaches need a hot and cool side?

[Peep18]

i bought a heatpad for my dubia roaches i just got. it fits under the whole bin do i need to leave a cool side for them?

 

[CooperDragon]

Not really. You can build upward by putting cardboard tubes on top of eachother. Most likely they'll bury themselves in the frass if they want warmth and they can move up the cardboard stack to get cooler if they wish. I have the opposite setup with an overhead heat projector and they tend to congregate around the middle of the stack under the heat bulb.