Can you put a beta in a 1 gallon tank without a filter?

Answer 1

Yes it can. One gallon is the recommended minimum but many people keep bettas in smaller tanks without problems. My personal opinion is that any fish is happier if you provide it with a simulation of its natural environment. Bettas are happier in small tanks with plants, gravel and decorations than large bare glass boxes.

Answer 2

Yes you can, but you have to be very careful about changing the water. You should change about 50% of the water every three or four days. Use a piece of air hose (very cheap) to drain the water into a bucket, then mix up the new water with dechlorinator and pour it slowly into the tank. Avoid huge temperature differences. While it is okay to keep a betta without a filter, it must have a heater. If it is kept in a centrally heated room it will be okay, but if the water temperature is likely to drop below about 18 degrees C, he needs to be in a heated bowl. A betta has a breathing organ called a labyrinth that allows it to cope with low oxygen content and dirtier water than any other fish will tolerate, but is a tropical fish that will not stand cold water.