The Siamese Fighting Fish (Betta splendens), also known as the “Betta”, is a freshwater fish native to Thailand (formerly Siam) and present in neighboring Cambodia, Laos, Malaysia, Indonesia, and Vietnam. While commonly known and marketed in the global aquarium trade as the “Betta”, it is one of 73 species in the genus Betta. Betta fish are among the most popular and widely available aquarium fish in the world, due to their varied and vibrant colours, diverse morphology, and relatively low maintenance.
Betta fish, especially the males, are usually aggressive in nature and are best kept separated from each other by using mesh separators or by keeping only one fish in a nano tank. Sorority tanks are possible with a group of female Betta fish but it requires experience and careful planning of the aquascape, and are not recommended for beginners. This article explores the setup of a simple nano tank with a single male Betta fish.
The Betta is a freshwater fish which thrives in shallow streams and rice paddies in Thailand with temperatures ranging between 75 and 82 degrees Fahrenheit or 24 and 28 degrees Celsius. The water should be clean and dissolved ammonia & nitrates should be as low as possible with the pH ranging between 6.5 and 7.5. The Betta primarily feeds on small insects in the wild and is considered to be carnivorous with regard to its diet. If properly kept, a Betta fish can survive for 5-7 years although, in captivity, it usually survives for 2-3 years only. Unlike most other fish, the Betta fish has a special organ called the labyrinth which allows it to survive by inhaling oxygen from the surface of the water. Although this means that the Betta fish can survive for extended periods of time without a filter, it is not recommended to do so. A filter is highly recommended to keep the water clean and healthy for the Betta. Care must be taken to ensure that the flow rate of the filter is not too high as Bettas like slow moving or stagnant water. A flow rate of 4x-5x the tank size is considered to be good enough for a Betta fish. If the Betta experiences difficulty in swimming due to its extended and flowery fins, we may use natural obstacles such as rocks and/or plants to slow down the flow of water. Bettas are also considered to be good jumpers. Hence, it is necessary to put a lid or net on top of the aquarium. However, if the water quality is good and the fish is not stressed, it is unlikely to jump. A tank size of around 5 gallons is considered to be the minimum necessity for a Betta fish. Bettas can survive in smallers tanks, bowls or vases for a short period of time but it will not lead a happy and healthy life.
There are several varieties of Betta fish in the aquarium trade, mostly classified on the basis of their tail types, finnage and colour: Veil Tail, Crown Tail, Comb Tail, Double Tail, Spade Tail, Half Moon, Over Half Moon, Delta, Elephant Ear, Plakat, Candy Nemo Plakat, etc. Of these varieites, the Half Moon, Over Half Moon, Delta, Elephant Ear and Plakat varieties are most popular.
Plakats are, in general, more aggressive than the Betta Splendens and should be handled with care. A good diet, clean water and plenty of hiding spots with live plants are absolutely essential for a Betta fish to thrive. In this article, we shall explore the basic setup only, without live plants. The selection and planting of plants in a Betta tank shall be explored in detail in a separate article.
For our setup, we have taken a glass cuboid of the following dimensions: 12 inches in length, 12 inches in breadth and 8 inches in height (5 gallons). Considering the water surface to be an inch below the top edge, this translates to roughly 4.3 gallons or 16 litres of water. Fine black gravel has been chosen as the substrate as it makes the Betta’s colour stand out while red lava rocks have been used for the hard scape to create a contrasting view. White vinyl has been used as the background for the tank. Fine black gravel and porous red lava rocks not only create a visually pleasing aquascape but also serve as excellent media for biological filtration. For filtration and aeration, we have used a suitably sized Hang on Back (HOB) filter to keep the water clean through mechanical and biological filtration. A 10 Watt full spectrum LED light provides sufficient illumination for this nano tank.
To kick-start the fishless Nitrogen cycle, we must first add a few pellets of fish food into the tank full of filtered water. Seachem Prime is used to dechlorinate the water in the new tank. Any other fish-safe dechlorinator would work equally well. This is followed by the addition of a one-time recommended dose of suspended bacteria solution such as Seachem Stability or Aquatic Remedies Microlife S2 or Prodibio BioDigest. Any product is fine as long as it is within the expiry date mentioned on the bottle. Care must be taken to ensure that the filter is always kept running as it helps in aeration and colonisation of beneficial bacteria. After 7 days, change 50% of the tank water and replace it with fresh dechlorinated and filtered water. Release the Betta fish into the tank and keep the lights off for the day so as not to stress him in his new environment. Add the recommended dose of suspended bacteria solution to the tank to keep ammonia and nitrites low and also to help the growth of beneficial bacteria in the biological media (filter pad, lava rocks & gravel). For the next 7 days, we must change 30-40% of the tank water daily followed by the addition of fresh dechlorinated water and bacterial suspension. Do not over-feed the Betta. 4 micro pellets of Betta food (Hikari Betta Bio-Gold) twice a day is sufficient to keep the fish healthy and active. By this time, the tank would be 2 weeks old. Reduce the water change frequency to twice a week while ensuring the same precautions; dechlorinated filtered water and bacterial suspension. Continue this for the next 2 weeks.
By the end of 1 month, the tank should be mature and the beneficial bacteria should have colonised the filter media and lava rocks. However, if we do not use any bacterial suspension, it may take 2-3 more weeks for the tank cycling to be complete. When in doubt, test the levels of ammonia, nitrite and nitrate with any available fresh water test kit (API). From the 5th week, we may further reduce the water change frequency to once a week. Adding an Indian Almond Leaf to the tank shall further improve the water quality and make the environment better for the Betta. Indian almond leaves leach tanins which have fantastic medicinal properties and can cure a variety of bacterial and fungal diseases. It also helps to lower the pH of the water which makes dissolved ammonia less harmful for the fish. You can further beautify the tank by adding live plants such as Anubias Nana Petite and Java Moss. Live plants beautify the tank, clean the water by absorbing nitrates and provide shelter and shade for the Betta. We shall explore the choice of plants in greater detail in the next article. The following video shows the full nano setup at a month’s maturity.