Well I have the 150 watt rheostat that I use for the heat pad of my Colombian Rainbow Boa. Unlike a thermostat, it doesnt make sure the pad stays at a specific temp, so you're going to have to adjust it to keep the temps right. Thermostats, on the other hand, make sure that the heating device stays at a certain temperature.
By the way, the rheostat has been working fine for my boa. I have a Cal King, but I never had the heating under any control and she's been fine for 3 or 4 years now.
I haven't been in this forum often lately. What kind of kings do you have?
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Scott
Reptiles
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0.0.1 Colombian Rainbow Boa (Rocky)
1.0 Ball Python (Sultan)
0.1 California Kingsnake (Leota)
1.0 Eastern Painted Turtle (Yugi)
0.1 Red/Gold Bearded Dragon* (Irwin, R.I.P.)
Other
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1.0 Betta Fish (Tyrone)