101 degrees is in the realm of normal for Flexwatt run wide open. Alot depends on the ambient air temp and the material of whatever the Flexwatt is resting on. I mean, if you laid Flexwatt on 1/4 inch thick aluminum I doubt it would ever reach 101 deg.

If the tubs have shavings or paper pulp bedding, you may feel little warmth on top of the substrate, since the warmer air is trapped under the substrate. It can be very warm under. Again, depends on the ambient air and material of the shelves. Particle board will suck away alot of heat in a cool room. Plastic shelves will not suck away as much.

Anyway, sounds like your connections are good.