One of the betta's distinct features is its ability to breathe oxygen in air and water, so aeration is not required. Decorate their home with gravel/colored stones, silk plants, and a small cave-like structure to hide. A creative home is a happy home! Add a gentle filter and small heater.
Avoid jagged rocks or decorations, as they tear betta fins.
Avoid hard plastic plants, as they can be rough on the fins. Use the 'pantyhose test': If a plastic plant will snag a pair of pantyhose when rubbed against it, then it will damage your betta's fins. Be safe and buy silk plants instead.
Anubias nanaWhile live plants aren't necessary, they are a great addition to betta tanks. They're prettier than fake ones, and bettas love lounging on the leaves and hiding in them to sleep.
Prepare the water. Use a water conditioner before putting fresh tap water in the tank, as chlorine and chloramines can harm bettas. Older sources may suggest aging the water (standing it for a time) but it's best to use a water conditioner, as aged water removes chlorine but not chloramine and heavy metals.
Fill your tank. If your tank is without a top cover, fill it about 80% high to ensure your fish won't leap out. Bettas are very active and can jump over 3 inches when motivated!
If your tank is without a top, use a mesh cloth on top to discourage jumping. Your betta will be much happier with the extra water and access to surface air.
Test the water temperature. Your tank must be maintained at a constant 78-82 degrees. A small heater is smart, as the water temperature is often much cooler than room temperature, and fluctuates easily.