How many gallons do 3 bettas need?

Quick Answer

3 betta fish need a minimum of 5 gallons each for a total of 15 gallons. Bettas are tropical freshwater fish that require adequate space and proper water conditions. The general rule is to provide at least 5 gallons per betta in a cycled, filtered, heated aquarium.

How Many Gallons for 1 Betta Fish?

The recommended minimum tank size for a single betta fish is 5 gallons. This allows enough room for the betta to swim and explore. It also makes it easier to maintain stable water parameters. Smaller tanks and bowls do not provide adequate space or water volume.

In a 5 gallon tank, there is sufficient dilution of waste products like ammonia. The nitrogen cycle works better in larger volumes of water. A 5 gallon tank can also accommodate a heater and filter more easily. These are essential for bettas to thrive.

Some key points on ideal betta tanks:

– Minimum 5 gallons for one betta
– Rectangular shaped, longer than tall
– Include hiding spots and plants
– Has filter and heater
– Maintain water between 78-82°F
– Weekly partial water changes

While bettas can survive short term in smaller containers, a 5 gallon or larger cycled tank allows them to truly thrive long term. It provides a safe, comfortable, stable home.

Betta Tank Size Guidelines

  • 1 betta: Minimum 5 gallons
  • 2 bettas: Minimum 10 gallons (divided tank)
  • 3 bettas: Minimum 15 gallons (divided)
  • 5 bettas: Minimum 25 gallons (divided)

These tank sizes account for the territorial nature of bettas. Male bettas will fight if housed together. A divided tank allows each male betta 5 gallons of personal space. Aggression is also reduced by breaking lines of sight. Female bettas may tolerate community tanks better. But sororities still require extra space.

Bigger is always better when it comes to fish tanks. Up to 10 gallons per betta provides even more room to swim and less concentrated waste. But 5 gallons per fish is the commonly recommended starting point.

Nitrogen Cycle and Water Changes

The nitrogen cycle is crucial in any aquarium. Fish waste and uneaten food produce ammonia. This ammonia is toxic but gets converted to nitrite by beneficial bacteria. Nitrite is then converted to safer nitrate. Both steps require established biological filtration (cycling a tank).

In an ideal cycled tank, ammonia and nitrite stay undetectable while nitrate accumulates over time. Performing partial water changes removes this nitrate before it reaches unsafe levels.

Cycling a tank properly takes 4-8 weeks for bacteria colonies to populate and convert ammonia/nitrite. Bettas should not be added until the cycle fully completes. An uncycled tank causes ammonia and nitrite spikes, severely stressing or killing fish.

Once cycled, a 5 gallon betta tank needs ~25% water changes 1-2 times per week. The frequency depends on exact stocking and feeding. Test kits allow tracking of ammonia, nitrite, nitrate to guide water change schedules.

Proper water changes are crucial, even in cycled tanks. The nitrogen cycle controls toxins but cannot eliminate them fully. Water changes restart the dilution process, resetting safe levels. This keeps bettas healthy long-term.

Choosing a Filter

Filters are mandatory in betta tanks. They provide flow, oxygenation and biological filtration. For 5-10 gallon betta tanks, simple low-flow hang-on-back (HOB) filters work well. Sponge filters are another quiet option.

Filters should turn over the tank volume at least 5 times per hour. So for a 5 gallon tank, the filter flow rate should be 25 gallons per hour (gph) or higher. Multiple media types are ideal, like a sponge combined with biomedia.

Always adjust flow to minimize stress on bettas’ large fins. Baffle the outlet with a sponge if needed. Position decor to provide calmer areas too. Avoid strong water currents that push bettas around.

Heaters and filters require brief maintenance like rinsing media monthly. But both run continuously to maintain water quality. Use a separate bucket during water changes to preserve beneficial bacteria.

Heating Betta Tanks

Warm water is critical for betta health. These tropical fish thrive best at 78-82°F. Colder temperatures compromise their immune systems and digestion. Bettas become lethargic and prone to disease under 74°F.

A 50 watt adjustable heater works well for 5-10 gallon betta tanks. Preset heaters can also be used. Place the heater horizontally near the filter outlet to maximize water flow and heating.

Maintain tank temperatures constantly in the ideal 78-82°F range. Use a separate thermometer to verify, as preset heater dials can be inaccurate. Perform water changes with similar temperature water to avoid shocks.

Avoid overheating above 84°F, as high temperatures stress bettas. If using smaller 2-5 watt heaters, use two horizontally spaced out for redundancy. Small heaters struggle to maintain stable temperatures alone.

Proper heating enables bettas to remain active, eat well and have proper metabolism. This supports health, coloration and long lifespan. Heating is just as vital as filtration for hobbyist betta keepers.

Selecting Tank Decor

While bettas appreciate open areas to swim, too much empty space stresses them. They evolved in heavily planted, complex environments full of hiding spots. Recreate this feel by adding plenty of plants and decor.

Live or silk plants are ideal as they do not tear delicate fins. Use a mix of stem plants, floating plants, carpet plants and broad leaf plants for variety. Place them spread out to break line of sight while allowing room to swim.

Add structural decor like driftwood, rocks and tunnels. Cave-like decor provides security, reducing stress. Avoid sharp decor that damages fins. Only use smooth, fish-safe products. Test paint and coatings by soaking decor for a few days.

Arrange decor for interest before adding your betta. Create spaces with both cover and open areas. Plants, rocks and driftwood can form natural looking territories and sight barriers. Adhesive tank backdrops bring themes like betta biotopes to life.

Tankmates for Bettas

Male betta fish should be kept alone in most cases. Due to high aggression toward their own species, divided tanks are safest for housing male bettas. Introducing tankmates risks stress or injury.

However, some community options do exist for betta tanks over 10 gallons:

  • Peaceful schooling fish like small tetras or rasboras
  • Bottom feeders like cory cats and snails
  • Shrimp like ghost shrimp or Amanos (may be eaten)

Avoid fin nippers like tiger barbs or guppies. Slow fish with long fins also draw betta attacks. Introduce any tankmates with extreme caution and backup plans. Observe for signs of aggression or stress in the betta.

Female bettas and betta sororities require more space. Generally 15-20 gallon heavily planted tanks are suggested if attempting betta communities. Even then, individual betta temperaments vary.

Ultimately, the simplest and safest option is keeping male bettas alone. This avoids dangerous conflicts while allowing your betta to be the featured star. Their personality really shines through in a solo tank.

Feeding Betta Fish

Bettas are carnivores, requiring a meaty diet. Flakes and pellets made for bettas or other carnivorous fish provide the best nutrition. Offer 2-4 small meals per day, only what they can eat within a few minutes.

Pellets made specifically for bettas are recommended as staple food. Top Fin, Hikari and Fluval all make betta diets. These pellets are high in protein and perfectly sized for bettas. Soak before feeding as they expand.

Alternate with frozen or freeze dried treats like bloodworms, brine shrimp or daphnia. This provides variety and enrichment. Avoid regular freeze dried foods due to risk of bloating.

Avoid overfeeding bettas, as excess food fouls water. Only feed what they can quickly consume to limit waste. Adjust feeding amounts based on appetite and body condition. Fasting 1 day a week helps digestion.

Setting Up a Betta Tank

Follow these steps when setting up a new betta tank:

  1. Select a 5+ gallon glass tank or acrylic kit. Rectangular shapes provide more surface area.
  2. Add a hang-on-back filter sized for the tank volume. Adjust flow to be gentle.
  3. Install an adjustable 25-50 watt aquarium heater. Verify temperatures.
  4. Add a natural substrate like fine gravel or sand.
  5. Include live plants like anubias, java fern, floating plants. Arrange decor.
  6. Fill slowly using a dechlorinator. Allow filter to run 1-2 weeks to cycle the tank.
  7. Test water parameters until 0 ammonia/nitrite and < 20 ppm nitrate.
  8. Acclimate the betta slowly by floating the bag and adding small amounts of tank water.
  9. Add the betta and begin a regular feeding/water change schedule!

Cycling the tank fully before adding fish is crucial. Testing water frequently also ensures the nitrogen cycle remains healthy long-term. This results in an ideal home for your new betta buddy.

Maintaining Stable Water Quality

Even in established tanks, water quality must be maintained through:

  • Partial water changes: 25% weekly, using a gravel vacuum.
  • Mechanical filtration: Rinsing filter media monthly in old tank water.
  • Chemical filtration: Using activated carbon or other chemical media.
  • Biological filtration: Never deep cleaning all filter media at once.
  • Testing: Tracking ammonia, nitrite, nitrate and pH weekly or more.
  • Additives: Using dechlorinator, beneficial bacteria and other supplements.

The nitrogen cycle manages toxins but does not eliminate them. Water changes should occur weekly in cycled tanks to dilute nitrate. Deep substrate cleaning is also needed monthly via gravel vacuuming.

Test kits allow close monitoring of the invisible nitrogen cycle. Noticeable spikes in ammonia or nitrite should trigger immediate partial water changes to correct the issue.

With regular care, 5 gallons provides a stable, comfortable environment for bettas to thrive. Good luck with your new betta buddy!


The standard recommendation for betta fish tank size is a minimum of 5 gallons per fish. This allows room for swimming, enrichment and stable water quality parameters.

To house 3 bettas, a 15 gallon divided tank is ideal. This provides 5 gallons of personal space per fish. Make sure the tank cycles fully before adding fish to establish healthy bacteria populations.

Maintain the 15 gallon tank with the following:

  • 25-50% weekly water changes
  • Adequate filtration and heating
  • Live plants and decor
  • Testing and correcting water parameters
  • High quality diet 2-4 times daily

With proper setup and care, 3 bettas can thrive together long term in a shared 15 gallon home. Pay close attention during tank introduction and rearrange decor to break up territories if needed. Enjoy their amazing colors and active personalities!

Leave a Comment