I am setting up a Herpstat 1 as my primary thermostat with a Ranco as my backup. It is being used on a eight position rack with 16 qt tubs. What differential temp should I use on the Ranco? I was thinking of initially setting my Ranco at 92 F (differential 1 degree) and my Herpstat at 90 F. I will increase the temperature (Ranco always two degrees warmer then Herpstat) until I get to a belly heat temperature of 90 F. Please tell me if this approach is correct.

Also, I currently do not have any ventilation holes. Do I need them? There is a bout a 1/16 inch gap between the top of the tubs and the rack. How many holes should I put in each tub to get started and them check my humidity.

Thanks