I'll bet Salmon Boas' room has a nice T-stat that keeps the room optimal.
The problem with running flex-watt by itself, and even in junction with a reostat is that if the room gets hotter,or cooler, then so does the cage. So you really can't keep the temps optimal without using a T-stat. Their are cheap T-stats, but they may fail, but if you buy two cheapo t-stats, and plug the flex-watt into the first T-stat, and plug the first T-stat into the second one , and set the second ond 5-10 degrees higher than the first, so if the first one quits , the second one will keep your Boas from frying.
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