i have kept americans at room temp ; 70-75 w/ no probs. personally, i dont use heat pads, i use oil heaters to add some extra temp to the room. key to toads is good substrate to burrow in and plenty of hiding places. if yours are thriving, then don't change a thing. cheers
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2 tham radix
1 Chicago Tham s. semifasciatus
2 elaphe vulpina
1 gray tiger sallie
4 Aphonopelma hentzi
2 G rosea
1 Haplo minax