Do tropical places need heaters?

Heaters. If you are keeping tropical fish, you will need a heater. A heater insures that a tank doesn't get too cool, and that the temperature stays steady during the course of the day, even when the room cools off (e.g., at night). For many tropical fish, a temperature of 78F is ideal. There are two main heater types. read more

And thus if you have tropical fish that can survive in the temperature range between 74.6°F and 85.4°F, you do not need an aquarium heater. Conclusion: Provided that the room temperature doesn't fall +0.4°F below the low limit and rise above the -0.4°F the upper limit, you can keep a tropical aquarium without heater. read more

Freshwater fish tanks need heat or not according to the type of fish being kept. Cold-water specimens don't require a heater, but not all freshwater fish can survive in cooler waters: some freshwater fish are tropical or sub-tropical. read more

First off, betta are tropical fish and need heaters unless you live in a very hot and humid place as they need temperatures above 76F. The only way you can have a fish tank without some form of climate control (heater or chiller) is if you have a certain area of you house that stays a pretty fixed temperature year-round. read more