Betta fish tank setup

Bettas are often sold as fish that can live in a bowl. They can't, at least not well. With the right simple setup, a betta can live 3 to 5 years and show far more color and personality.

Tank size: 5 gallons or more

A betta needs at least 5 gallons. Bigger tanks hold temperature better and dilute waste, so a 10 gallon is even easier. Bowls and vases are too small to heat or filter, and water quality drops fast. Not sure of the size? Use the volume calculator.

What you need

• Heater: bettas are tropical fish. Keep the water at 78–80°F. A 25–50 watt adjustable heater suits a 5–10 gallon tank.
• Gentle filter: bettas have long fins and get pushed around by strong currents. A sponge filter or an adjustable filter on its lowest setting works well.
• Lid: bettas can jump. Leave a small gap of air above the water, because they breathe from the surface.
• Thermometer and water conditioner.
• Soft decorations: live or silk plants. Run a pair of tights over any plastic decoration; if it snags, it can tear fins.
• A resting spot near the surface: a floating log, a broad leaf, or a "betta hammock".

Setup steps

1. Set up the tank with substrate, plants, filter and heater.
2. Cycle the tank before adding your betta.
3. Float the betta's cup in the tank for 15 minutes, add small amounts of tank water over the next 15 minutes, then gently net it in.
4. Leave the light off for the rest of the day.

Feeding

Feed 2–4 betta pellets once or twice a day. Their stomach is about the size of their eye, so it's easy to overfeed. Frozen or freeze-dried bloodworms make a good treat once or twice a week. Skipping one day a week helps avoid bloating.

Can bettas have tankmates?

Never put two male bettas together. Some bettas are happy with peaceful company in a tank of 10 gallons or more, but each betta has its own personality, so have a backup plan.

• Usually good: nerite snails, mystery snails, ember tetras, pygmy corydoras, harlequin rasboras.
• Avoid: fin nippers like tiger barbs and serpae tetras, other bettas, gouramis, and colorful long-finned fish like guppies, which bettas may attack.

Check any combination with the stocking calculator.

Weekly care

Change about 25% of the water each week, using conditioner and water at the same temperature. In a small tank, weekly changes matter even more because waste builds up faster.

Common betta problems

• Lying on the bottom, faded color: often cold water. Check the heater and thermometer.
• Ragged, shrinking fins: fin rot from poor water quality, or snags on sharp decorations.
• Bloated belly: usually overfeeding. Fast for a day or two and feed less.
• A pile of bubbles at the surface: a bubble nest. It's a sign of a happy male, not a problem.