hm. so proportional is not really necessary? I just want to make sure my captives are as happy and healthy as possible. I am used to keeping fish and temperature swings are very stressful for them. But if a BP doesn't mind, then an on/off thermostat might be the economical way to go.

Also, what do you recommend for heating? I see some with lights, some with the lightless ceramic heaters. What do you think?