The problems with a betta bowl

There are 3 main problems with bowls for bettas:

1. Bowls are generally quite small.  A betta, just like any other fish, should be kept in a larger volume of water than a bowl can provide to prevent the rapid build up of toxins and organic compounds from the fish and fish food.
2. Bowls are not heated.  Bettas are tropical fish.  They need the water to be between 76F and 82F, which is generally not achievable, at least steadily, without a heater.
3. Bowls are not filtered.  Filtering provides a mechanism for the nitrogen cycle to process ammonia and nitrite.  This is generally off set with frequent changes of the water in the bowl.

Why do stores sell bowls if they should not go in a bowl?

Simple: stores sell betta bowls because people buy them.  Unlike many other pets, there isn’t a big industry built up around preventing abuse and neglect for pet fish.  And the reality is, it keeps people coming back for more.  If you buy a bowl and a betta, the betta will live for some period of time – 6 months, maybe even a year or two.  After that, you’ll come back to buy another betta.  Additionally, selling bowls really expands their customer base.  Relatively speaking, there are not a lot of people who want a big aquarium in their house, but there are many more that find a decorative bowl acceptible.

Post from: Tropical Fish Central

Can a Betta Live in A Bowl?