It looks like the Catalina is just a rheostat??? A probed thermostat couldn't run three different heat mats, because they could be all heating at different rates.
People with large collections seem to use heat tape. I have no experience with it so hopefully someone can explain.
Heya ,in england everyone I know who keeps snakes including me use these , they are the only ones the pet shops sell and they work great View attachment 183457
I have never heard of them, but I think your electrical outlets are different from ours. Someone had recommended some from Australia but the plug was different and something like this I don't want to chance with converters.