Betta Fish Care: Selecting a Fish, Tank, and Equipment

Betta fish are often chosen by first time fish owners because they are highly attractive, display an interesting array of behavior, and are generally hardy fish.

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Male betta fish typically have long, flowing fins and they come in a wide variety of colors and patterns. Their bodies are often iridescent adding to an overall very beautiful appearance. And when they see their reflection or other stimuli that alarm or interest them they will "flare" by spreading their fins outwards to look bigger, and perform a dramatic territorial display.

Betta fish have great personalities. They also show a lot of interest in changes in their environment. Bettas will investigate any changes in their tank, and be attracted towards movement outside their tank. They also seem to enjoy moving around, under, and through any plants and other objects in their tank. If provided with a soft surface like a plant or "betta hammock" they will often rest on top of it.

For these reasons betta fish are a very popular choice both for people starting their first aquarium and for experienced fish-keepers.

Betta fish have the ability to breath air, and so may tolerate temporary reductions in water oxygenation ("stagnant" water). The have proven tolerant of shipping and the problems with water quality that may occur when first setting up a new fish tank. However, like any fish, they do need water free of toxins and maintained at an appropriate temperature and oxygenation level.

Choose a fish you find attractive by all means, but avoid fish with a tail so large it impedes their ability to move around--especially the so-called "rosetail" which may actually collapse under its own weight.

Avoid buying from locations were many of the fish seem lethargic, ill or are even dead. Select a fish that is active and reactive to its environment. Buying younger fish may help the fish adjust to its new life with you, and give you the longest possible time with your new pet.

Males often have the largest fins, however they can not be kept with other betta fish. Females are also very attractive and come in many colors. Females bought at the same time will generally live in groups (called "harems"). However introducing a new female to a group can lead to aggression.

Both males and female vary in how well they adapt to being housed with other fish and invertebrates. Some are very aggressive or have a very strong prey drive and will harass tank mates. However others will live peacefully, especially with small peaceful fish that do not have long fins.

Size: Many small tanks are sold for Betta fish and these fish can survive in very small amounts of water. However it is wise to give them a bit more space to provide them with activities, room to move around, room for tank décor and appliances, and a larger amount of water that will have more stable chemistry. Small quantities of water can change temperature quickly and rapidly build up waste products which can stress your fish.

A good lower size limit is a case of judgment and opinion, so this is mine: A four gallon tank is a good lower limit. A 4 gallon cube can accommodate a filter and air-stone, but leave enough still water space for the fish to rest. It also still takes up quite a small area and so can easily be kept on a shelf or desk. I personally prefer the Fluval Chi II, an attractive 5 gallon tank.

A sorority of three female bettas can do very well in a tank as small as 10 gallons, however it is a good idea to have it well planted or decorated to allow fish to get away from each other in the even of conflict. Keep in mind that the volume tanks are reported to have reflects the external dimensions, the real capacity will often be about a half gallon less.

Materials: The main options are acrylic which is light but can easily be scratched, and glass which is heavy, and sharp if broken, but cannot be scratched by most normal tank cleaning equipment or décor. I lean towards glass as a nicer look and more durable choice. It is slightly more expensive but a 4-10 gallon tank can be found for less than $20 new and just a few dollars second hand. Make sure you calculate the size of the tank yourself as sizes are often mis-represented on the second hand market.

Yes, even a small tank will need either an airstone or a filter. I you change the water frequently (and I don't mean just "intend to" do it, but will actually make it part of your routine) you can get buy with an airstone set to a low level of flow. Because betta fish do not live in flowing water there needs to be still areas in the tank. It helps if there are plants and/or décor in the tank to help break up water currents. However there does need to be some movement in the water to keep it aerated and promote good water conditions. So get an air stone and air pump suitable for a small tank and with an adjustable flow so you can set it at the ideal rate for you tank.

You can attach a simple filter to a airstone, or have a separate filter either hanging on the side of the tank or submersed. If you prefer a submersed filter choose a small model so as not to use up to much tank space.

You tank should be kept at 76-82 Fahrenheit. Do not use a heater that is located outside the tank as the results are unreliable. If you wish to depend on ambient room temperature be sure to actually measure room temperature rather than just assume it is within this range 24 hours a day, 365 days a year. Small in-tank heaters are available that are pre-set to a certain temperature or adjustable. Again, if you have a small tank go for smaller options to avoid taking up too much tank space. In my experience all reputable brands deliver a similar high level of performance.