Provided your daytime temperatures get warm enough, then there is little need to worry about your nighttime temperatures. My nighttime temperatures regularly get into the upper 60s with no apparent ill effects on my monitors, and I have done this for many years. I have had occasions where the nighttime temperatures have fallen into the low 60s with no apparent problems, although such lows do make me uneasy and I work to avoid them. That uneasiness is simply my feeling, it is quite possible that low 60s are not detrimental either, but I am not comfortable with those temperatures.
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^x^ Bloodbat ^x^
Monitors, monitors everywhere
and all the food they ate.
Monitors, monitors everywhere,
their parents loved to mate.