Yesterday there was a power failure and my aquarium temperature rose to
nearly 30 degrees C (90 F) The forecast is for a prolonged hot spell
with temperatures in the high 30s (degrees C) = 100 degrees F

The local pet shop owner reported that the fish jump out of her tanks if
it gets too hot.
Any suggestions on how to manage an aquarium during hot weather? (with
or without a power failure.)

David F