Betta Fish Fins

Bettas use their fins not only to move through the water, but also to steer and to maintain their balance. The fins are composed of long rays with skin stretched thinly between them. Special muscles attached to the rays provide control. Your Betta’s fins include one caudal fin, one dorsal fin, two pelvic fins, one anal fin, and two pectoral fins.

The caudal or tail fin, combined with the muscular tail stalk, provides the force for sudden forward bursts of speed and for fast swimming. In fancy Bettas, such as the splendens varieties, the lengthening of the natural caudal fin through artificial selection (breeding for a specific trait) has resulted in a slower-moving species than its native relative.

The sole purpose of the dorsal fin (located on the upper back region) and the anal fin (on the bottom) is to give the Betta stability, in the same way the tail assembly on an airplane keeps it stable. These fins keep your Betta in an upright position and prevent it from literally rolling over in the water.

Pectoral fins also provide stability while moving through the water and help the fish steer. Located near the bottom of the fish, directly beneath the gill openings, the pectoral fins can also be used by the male Betta to fan its incubating eggs, bathing them with fresh water to eliminate wastes and debris.

Pelvic fins are located on the hip area and also aid in stabilization and steering.

Betta Fish Swim Bladder

The Betta’s body weighs slightly more than the volume of water it displaces, so it tends to sink. So, like many other fish, the Betta has a gas-filled swim bladder that functions as a flotation device.

By making minor adjustments to the gas pressure inside the swim bladder, the Betta can remain suspended (neutrally buoyant) with little or no effort. If the Betta moves to the bottom of the tank, its swim bladder will be compressed and it will begin to sink. To correct this problem, the Betta must either add gas to its swim bladder to achieve neutral buoyancy again, or use energy to swim upward.

The opposite is true when the Betta moves toward the top of the tank. There, it must release gas from the swim bladder or must use energy to return to a deeper depth. Gas enters or leaves the swim bladder via a specialized duct. As the Betta moves about in its watery realm, small changes inside its body, unseen by the human eye, automatically maintain the proper buoyancy.

Betta Fish Scales

Scales cover the Betta’s body, overlapping each other like the shingles on the roof of a house. These thin, transparent scales help protect the Betta’s body from injury and streamline the fish for efficient swimming. A mucus layer covers the scales, reducing drag as the fish swims (this is the slimy feeling you get when you hold a fish in your hands). The mucus also helps protect against invading parasites and infection.

The Betta’s scales lack pigment. Its brilliant colors actually come from pigment cells located in the skin. The skin also produces both the scales and the mucus covering.

The Betta’s Lifestyle

Bettas prefer warm temperatures and gentle currents. They feel most secure when the aquarium provides plants that root in the bottom as well as plants that float on the surface. Betta tankmates should be non-aggressive fish that won’t harass the Betta or nip its fins. Bettas feed on a variety of small insects, mosquito larvae, and worms that they pluck from the surface of the water. In the aquarium they thrive on flakes, freeze-dried and frozen brine shrimp, live mosquito larvae, or other foods that tend to stay near the top of the water column.

Betta Fish Mouth Structure

The shape of a fish’s mouth may largely determine its mode of life. For example, you’ll find a turned-down mouth (inferior position) on bottom-dwelling species such as Catfish. These fish feed in mud, sand, or gravel, and off flat rock surfaces and plant leaves. A mouth located in the terminal position points directly forward from the fish’s face. Common among species such as Guppies and Platys that swim in midwater levels, a terminal mouth facilitates “picking off ” food as it sinks toward the bottom or floats in the water column.

The Betta’s upturned mouth, known as the superior mouth position, enables it to feed efficiently at the surface. Bettas snatch small insects and mosquito larvae from among the floating vegetation in the pond or paddy. They also greedily scoop up flakes at the top of the aquarium.

Always take care to ensure that your Betta receives its fair share of nourishment, especially if it is living in a tank with faster swimming, more aggressive fishes. Add food that sinks together with food that remains on the surface. Don’t force your Betta to compete with mid- and bottom-dwelling tankmates at feeding time.

Betta Fish Body Shape

A Betta’s streamlined body enables it to slip smoothly and effortlessly through the water. The tapered shape reduces friction, conserving the Betta’s energy as it quickly moves to catch its prey. Fish that have a more rounded shape, such as fancy Goldfish, swim more slowly and tire easily. Such fish often live in running water, where the current can aid their movements.

Fish that live in stagnant or slow-moving waters in their natural habitat develop a flattened, compressed body shape to facilitate gliding through stands of the upright reeds and plants that also favor such environments. The Discus (Symphysodon), which lives in quiet shallows along the Amazon River, provides a similar example. In fast-running water, a fish shaped like the Discus would get tossed about in the current like a leaf.

What Is a Betta Fish?

Ichthyologists (people who study fish) classify fish based on body form and structure. They group species in a hierarchy of ever more inclusive categories, from individual species such as Betta splendens to families (such as anabantids, which are fish with a labyrinth organ), to a large class, Pisces, that includes all fish. Fish represent but one class of vertebrates (animals with backbones, including humans). Other vertebrate traits include a brain case (skull) and a skeleton that protects the internal organs and supports the body weight.

Like all fish, the Betta breathes through external gills. Like other anabantids, it also has the labyrinth organ that enables it to use atmospheric air.