The Betta splendens is one of the most popular species in the aquarium trade in the Western world. Known for their brilliant colors and long, flowing fins, betta fish are fairly easy to care for, but novice aquarium hobbyists sometimes get confused about what type of water to use in a betta tank. As is true in regard to all aquarium fish, the type of water used in the betta tank can greatly impact the fishes' health.
Recommended Tank Size
Because betta fish are often sold in small jars or plastic containers, many people mistakenly think that these fish can thrive in such a small environment. While a betta fish may become nervous in a tank that is too large, small bowls don't provide adequate space for healthy growth. The recommended tank size for a betta fish is between one and five gallons. Betta fish aren't as active as some species of freshwater fish and don't require a great deal of swimming space, but a tiny tank can result in a dangerous accumulation of waste and toxins.
Distillation is a purification process that can be applied to water. This process utilizes a heat source to vaporize the water, separating the water molecules from the dissolved contaminants. Though distilled water is pure and free of contaminants, it is also devoid of minerals. Because minerals are essential for maintaining healthy coloration, skin and fins, betta fish that are kept in distilled water may exhibit a loss of coloration and can become lethargic over time. For these reasons, using distilled water in a betta tank is not recommended.
Plain tap water is the most recommended -- and inexpensive -- option for betta tanks. Because most tap water is treated with chemicals, however, you may need to condition the water before adding it to your tank. Use a small amount of water conditioner according to the manufacturer's instructions -- many products have a dosage of one teaspoon per 10 gallons of water. A small betta tank, then, may require only a few drops.
In addition to selecting the right kind of water for your betta tank, you also need to monitor the water parameters such as the temperature, pH and water hardness. The recommended temperature for a betta tank is between 75 and 86 degrees Fahrenheit, or 24 to 30 degrees Celsius. Bettas prefer a pH between 6.5 and 7.5 and a water hardness between 5 and 25 dGH. To monitor the water parameters in your betta tank, perform weekly water tests. Weekly water changes help to keep the tank parameters stable and the water clean so your betta fish can thrive.
Change about 25 percent of the water in your betta tank once a week to keep the water quality in the tank high. If you're keeping your betta in a bowl or a tank without a filter, perform more frequent water changes. Before you change the water, net your betta and place him in a temporary holding tank. Use an aquarium gravel vacuum to siphon the gravel in the tank, removing waste build-up while also draining the tank. Once you have drained 25 percent of the tank volume, refill the tank with tap water treated with a dechlorinating solution and return your betta to his tank. To avoid shocking your fish, the new water must be the same temperature as water in the tank.