Betta Fish
The Siamese Fighting Fish — the most abused fish in the aquarium hobby, and the most beautiful when cared for correctly. Those flowing fins, those iridescent colors, that labyrinth organ that lets them breathe air. Complete guide: why a bowl is a DEATH SENTENCE (5+ gallons minimum, heater mandatory), the truth about keeping Bettas with other fish, and the 20+ fin types.
📋 Species Overview
🌡️ Water Parameters
📑 Table of Contents
⚠️ The Bowl Myth — Why 5 Gallons/20 Liters Is the MINIMUM
This is the #1 most important thing about Betta care. Bettas are routinely kept in tiny bowls, vases, and cups — and they suffer and die prematurely in these conditions. A Betta in a bowl is living in its own toilet waste. Ammonia builds up within HOURS in an unfiltered, unheated container. Minimum tank size: 5 US gallons (20 liters) with a gentle filter and a heater. Bettas are TROPICAL fish — they need 25-27°C (78-80°F) water. Without a heater, they're cold, lethargic, and immunocompromised. A bowl is a slow death sentence. Pet stores that sell Bettas in cups are not your guide to proper care.
🫁 The Labyrinth Organ — They Breathe AIR!
Bettas are labyrinth fish (suborder Anabantoidei) — they have a specialized organ above their gills that allows them to breathe atmospheric oxygen. This adaptation evolved in the oxygen-poor rice paddies and slow-moving waters of Thailand, Cambodia, and Vietnam. It means Bettas can survive in water that would kill other fish — but it also means they MUST have access to the water surface. Never fill a Betta tank to the very top with no air gap. The labyrinth organ is also why Bettas can be kept without aeration — but they still need filtration (gentle, low-flow) and heating.
🏠 Tank Setup — Heater, Filter, Plants
- Heater: Absolutely MANDATORY. Set to 25-27°C (78-80°F). Below 24°C = stressed, immunocompromised Betta
- Filter: Sponge filter or low-flow HOB. Bettas HATE strong current — their long fins make swimming in current exhausting. Baffle the outflow if needed
- Substrate: Sand or smooth gravel (sharp gravel tears fins)
- Plants: Live plants (Java fern, Anubias, Amazon sword) or silk plants. NEVER plastic plants — they tear delicate fins. Bettas need resting spots near the surface (betta leaf hammocks, floating plants)
- Lighting: 8-10 hours daily — too much light causes algae and stresses Bettas
- Lid: Bettas JUMP — a tight-fitting lid is essential
🐠 Tank Mates — What CAN Live With Bettas
⚠️ MALE Bettas must NEVER be kept together. They will fight to the death — hence "Siamese Fighting Fish." Female Bettas can be kept in sororities (5+ females in a 20+ gallon heavily planted tank) but this is for experienced keepers only.
🍽️ Diet & Feeding
Bettas are carnivorous/insectivorous — in the wild they eat insects, larvae, and small crustaceans. Quality diet: high-protein Betta-specific pellets (35%+ protein), frozen/live foods (bloodworms, brine shrimp, daphnia — 2-3× weekly), and occasional fast day (1 day/week). How much: 2-4 pellets 2× daily — their stomach is the size of their EYE. Overfeeding is the #1 cause of bloat, constipation, and dropsy. Soak dry pellets for 5 minutes before feeding — dry pellets expand in the stomach and can cause blockages.
🎨 Fin Types — 20+ Varieties
Veiltail
Most common
Crowntail
Spiky rays
Halfmoon
180° spread
Plakat
Short-fin, wild type
Koi/Nemo
Marbled tricolor
Dumbo/Rose
Enlarged pectorals
🏥 Common Diseases & Treatment
- Fin Rot: Ragged, deteriorating fins — caused by poor water quality. Treatment: daily water changes + aquarium salt + antibiotics if severe
- Ich (White Spot): White dots on body/fins — parasite. Treatment: raise temp to 30°C (86°F) slowly + ich medication
- Velvet: Gold/rust dust-like coating — parasite, often fatal. Treatment: copper-based medication, complete darkness (parasite needs light)
- Dropsy: Pinecone-like raised scales, bloating — organ failure, usually fatal. Prevention is the only real cure.
- Swim Bladder Disorder: Floating sideways, unable to dive. Often from overfeeding/constipation. Fast 2-3 days, then feed daphnia (natural laxative)
🫧 Breeding — Bubble Nests
Male Bettas build bubble nests at the water surface — a sign of health and sexual maturity. Breeding requires: conditioned pair, separate introduction, 10+ gallon breeding tank at 28°C, and the male wraps around the female to fertilize eggs as she releases them. The male collects the eggs and places them in the bubble nest. Remove the female immediately after spawning — the male will attack her. The male guards the nest until fry become free-swimming (3-4 days), then remove the male too. Fry require infusoria or commercial fry food for the first 2 weeks.
💰 Cost Breakdown
💡 Fun Facts
National aquatic animal of Thailand: The Betta is Thailand's official national aquatic animal. Ancient Thai warriors bred them for fighting — the name "Betta" comes from an ancient warrior clan called the "Bettah."
They DROWN without air: The labyrinth organ means Bettas MUST surface to breathe atmospheric air. If a Betta cannot reach the surface, it will literally drown — even in perfectly oxygenated water.
Cold water = immunocompromised: Below 24°C, a Betta's metabolism and immune system crash. Room-temperature water in most homes (20-22°C) is too cold. This is why "bowl Bettas" die after months of slow suffering.
Each Betta has a unique personality: Unlike most fish, Bettas recognize their owners, can be trained to jump for food, flare on command, and some will even allow gentle petting. Their individual personality is remarkably developed.