Humidity is the red-eyed tree frog's emergency, not just heat
A red-eyed tree frog losing power to its heater and mister faces drying air before it faces real cold. This species breathes and drinks through its skin, so an enclosure that drifts dry stresses a red-eyed tree frog faster than one that drifts a few degrees cool. Keep the doors shut, cover a good part of the mesh top with a clean damp towel, and mist the walls and leaves with dechlorinated water whenever the glass starts to look dry. If the frog has a shallow water dish, top it up with dechlorinated water as well, because a red-eyed tree frog will sit in it to rehydrate. Chlorinated tap water straight from the tap is a poor substitute on skin this permeable, so use treated or rested water if you keep any ready.
Placing the tank where the house still helps
Where the enclosure sits decides how fast a red-eyed tree frog's conditions slide during an outage. Move the tank into the smallest room that people are actually occupying, since body heat and closed doors hold that air warmer and more humid than an empty spare room. Keep it off the floor if the floor is tiled and cold, away from windows where night air leaks in, and out of any draft from a door being opened to check on the house. Do not move the frog itself into a smaller tub to save warmth; a red-eyed tree frog stressed by capture and a bare container loses the humidity of its planted enclosure, which is the very thing protecting it.
Hands off, lights off, routine quiet
A red-eyed tree frog should not be handled during a power cut at all. Its skin takes up salts and oils from human hands readily, and every capture burns energy a cold, dry frog needs for simply sitting still. Leave the enclosure dark rather than shining torches in repeatedly; this is a nocturnal frog, and bright checks every few minutes disturb the rest that conserves its reserves. Feed nothing during the outage either, because live insects left loose in a cool enclosure may nibble at a sluggish frog, and a red-eyed tree frog that is too cool will not hunt them anyway. Quiet, dark, damp and undisturbed is the whole prescription while the equipment is dead.
Signs the frog needs more than waiting
A red-eyed tree frog coping with an outage stays perched or tucked against a leaf or the glass, skin moist, and wakes sluggishly if the enclosure is moved. Signs that waiting is no longer enough include skin that looks dry or dull and stays that way after misting, a frog slumped on the enclosure floor rather than climbing, or one that does not react at all to gentle movement of its perch. If the outage stretches long and the room itself turns genuinely cold, a frog showing those signs should be discussed with a reptile vet by phone rather than warmed rapidly, because fast reheating shocks a chilled amphibian as surely as the cold does. Once power returns, restore heat gradually and restart the mister before offering food the following evening.
One shared set of frog notes for everyone helping
Outages pull in helpers who mean well but guess: a partner who mists with the wrong water, a housemate who helpfully moves the tank to a cold hallway. The frog's exact routine, its treated-water rule, its normal temperature range and its no-handling note, needs to be in front of whoever is standing at the enclosure. KinsLe's Family Sharing puts that red-eyed tree frog profile and its care details in every helper's hands at once, so the person checking at midnight follows the same instructions as the person who set the tank up.