Why do Betta Fish Make Bubbles?
A healthy Siamese fighting fish or Betta Fish as it is commonly called will make bubble on the surface of the water. You do not have to worry about this because this is a sign that the fish is healthy and content with the way things are in his territory. It thinks that his place and the conditions around it are good enough to raise baby Bettas. In other words, these bubbles are nurseries for future Bettas.
However, do not go out right away and purchase a female fish to mate with him. It may just wreak havoc in his once peaceful environment. They might just do each other harm instead of making more babies not unless you are trained to breed this kind of ferocious fishes.
Not having a female in his tank is perfectly fine with your male fish. He will just go on and make these cute bubbles thinking and hoping that a female fish will suddenly appear out of nowhere. You can think of the bubbles as a sign of appreciation of the fish for taking care of it.
The bubble making rate of a Betta fish depends upon certain conditions like health of the fish and the environment that it lives in. Some fish make bubbles often every month and some make only a few each year. A healthy male Betta tend to make more bubble nests often so you can consider it as a sign of his health when you see him make this regularly. However, few bubble nests do not necessarily mean a sickly fish. The water conditions may be affecting his ability to make bubbles so you can check on that.
Although Betta fishes can survive in waters with low oxygen levels, it is still better to keep the tank clean and installing a filtration system and a few decorations.
A healthy Betta will give you a steady supply of these bubbles.