How does temperature affect the behaviour of fish in an aquarium?
Temperature effects metabolism and will vary behaviour wise species to species depending on how they evolved, i.e. Goldfish were built for cool temperatures, their metabolism works best at around 68F. If they’re colder their metabolism will slow right down, pond Goldfish and Koi in the winter will go into a form of hibernation and won’t feed until spring. When they’re too warm their metabolism works too quickly, they become very active and their metabolism struggles to keep up! Tropical fish, like Discus who prefer VERY warm temperatures at around 86F, their metabolism works best when they are very warm, too cold and it will cause them to be unable to digest their food properly, they’ll become very lethargic and they’ll die.