Betta Fish Care Tips And Guide
Bettas are often kept in extremely small containers, a practice which many aquarists consider inhumane. This practice is due in part to practical considerations; few pet stores have the space or finances to display a large selection of male bettas except in small containers. However, many inexperienced fishkeepers continue to house bettas in small containers after purchase. A popular misconception is that wild bettas live in very small puddles, and thus are "happier" when kept in cramped conditions. In reality, like any other fish, bettas are healthier, more active and will often grow larger when they are kept in a roomy tank. Aquarists typically recommend that there be at least 1 gallon of water for each cubic inch of fish (this is a general estimate; some species may require additional space).
Bettas enjoy plastic plants and small ornaments they can rest on. Many bettas also like ornaments with small openings they can swim in and out of. However, especially with veiltails, plants and ornaments need to be free of sharp edges to prevent the betta from tearing its fins.
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For more information on happy betta living conditions take look at Caring for Betta Fish by Marcus Song.