How Long Can Betta Fish Go Without Food?

So you have your vacation booked and your bags packed. But what about your Betta? How long can Betta Fish go without food?

Generally, a healthy adult Betta can go from 10 to 14 days without nourishment, but that is contingent on some very important factors.

Before you say goodbye to your beloved aquatic pal, read on for vital information on how to keep your Betta alive while you’re away. 

betta fish feeding

How Long Can Betta Fish Go Without Food? 3 Things to Consider

As we mentioned earlier, you can leave a healthy adult Betta without food for 10 to 14 days. But remember, the stomach of this fish is only about the size of its eye, so before you lock the door for your vacation, take a look at the following areas that will factor into Betta’s chances of survival on this extended fast. 

1. Aquarium Size

Small tanks (5 gallons and under) need their water changed more often, so if you leave for 10 to 14 days, the water quality can quickly change from optimal (in pH and ammonia) to lethal. The larger the tank with fewer tank mates will help ensure the survival of your Betta fish when you are away. 

2. Filtered or Unfiltered Aquarium

If your Betta is living in a bowl, know that this type of unfiltered container will turn lethal in a matter of days. Filters help reduce ammonia and keep debris from over-accumulating. To ensure the health of your Betta use an aquarium that can be maintained by a filter system

3. Health of Your Betta Fish

Young, healthy Bettas with plenty of fat reserves will be able to handle an extended fast better than older ones. Of course, all fish are individuals. How one Betta responds to stress, poor water conditions, and the lack of food, may not be how another Betta reacts.

Putting your Betta on a 10 to 14 day fast is taxing on the fish regardless of his age, so only do this when you have absolutely no other alternative!

Fasting Chart Comparison – 3 Days vs 14 Days

Generally, an adult Betta can survive a 3-day fast quite nicely. However, 14 days is another story. Take a look at this quick comparison chart for fasting your Betta for 3 to 4 days versus 10 to 14 days.

Fasting 3 to 4 Days

Level of Hunger? 

  • Normal
  • Will swim to the surface often in search of food

Stress Level?

  • May be slightly elevated

Water Conditions?

  • Normal (even unfiltered)


  • Peaceful to slightly elevated
  • May flare at other tank mates


  • Normal with flowing fins

Fasting 10 to 14 Days

Level of Hunger?

  • Very hungry – the body will begin starvation-mode
  • Will start to use fat stores

Stress Level?

  • Very stressed
  • Now at risk for disease

Water Conditions?

  • Needs a water change


  • Lethargic
  • Will hide more
  • Betta is vulnerable


  • Dull with clamped fins

7 Must-Dos When Leaving a Betta Fish

Whether you are leaving for only a few days or a couple of weeks, to better help your Betta through this time period, we recommend the following 7 must-dos.

1. Optimize Aquarium Conditions

We recommend getting your Betta tank to its optimal level before leaving. With a planned vacation here are steps to take and tasks to perform at timed intervals.

One week before vacation:

  • Check your filter for clogs and change the filter media. 
  • Siphon your substrate, cleaning up any debris and leftover food
  • Check the pH level – it should be between 6.8 and 7.5
  • Remove any dead plant matter and trim the plants back
  • Check all tank equipment like pumps, heater, filter, light, etc.

Day of leaving (done in both planned and emergency absences):

  • Water temperature should be between 75 and 80 degrees Fahrenheit
  • Perform a larger water change (even if it’s a community tank) – 80% for 5 gallons and under – 50% for 10 gallons and more. 
  • Check your Betta for health
  • Feed your Betta right before you leave (using the same amount as usual).
  • Make sure your aquarium lid is secure to prevent your Betta from jumping out.
  • Be sure no floating plants are obstructing the filter and heater or taking up too much surface space of the aquarium (your Betta likes to get oxygen from the top of the tank). 

2. Check the Heater

Bettas prefer a tropical temperature between 75 and 80 degrees Fahrenheit. Be sure your heater is fixed at this temperature to ensure there are no dips or spikes in the aquarium environment. 

If your tank is not heated, do not place it in front of direct sunlight as this will cause intense fluctuations in the water temperature and may cause disease and stress in your Betta.

3. Use Cooler Water for 10 to 14 Day Absences.

Even though Bettas do prefer tropical conditions, for long periods, use the cooler water to help slow down your Bettas metabolism and therefore its need to eat

The range you are aiming for is between 73 and 75 degrees Fahrenheit. Submersible heaters can be set for this temperature or the ambient temp of your home may be able to sustain this cool-optimal level.

Although not ideal, it is better for your Betta to be a bit sluggish and less hungry for 10 to 14 days, than to enter into starvation mode after 4 or 5 days.

4. Use a Timer on the Aquarium Light

To help your Betta maintain “business as usual” while you are away, use a timer to create an 8 to 10-hour daylight schedule. This will allow your fish to explore during the day and rest at night.

5. Secure the Aquarium Lid

Betta’s are notorious for leaping out of the tank and might be more apt to do so when the water conditions are not ideal and there is no food being dropped in. To ensure your fish doesn’t end up on the floor or the table, have a secure lid in place. You can also drop the water level, making it more difficult to breach the surface. 

6. Make Sure There’s Enough “Natural” Oxygen

The Betta is a part of the group of fish from the Anabantoidei suborder, meaning they have a labyrinth organ that allows them to breathe oxygen from the surface of the tank. 

Ensure your Betta can utilize this mechanism when you are away by anchoring floating plants and removing any clutter that may prevent him from surfacing the aquarium. If you are using an aquarium lid, make sure it contains unobstructed ventilation areas.

7. Do a Health Check on Your Betta

Leaving a healthy Betta for 14 days is going to be tough on the pet but an unhealthy fish will most likely not make it through this kind of stress.

Here is what a healthy Betta versus a sick Betta looks like;


  • Vibrant color
  • Flowing fins
  • Active, exploring the tank
  • Will flair at other fish or objects
  • No obvious signs of disease


  • Not as active or showing abnormal swimming patterns
  • Lethargic and hiding more
  • Dull color
  • Clamped fins or fins with ragged edges
  • Bloated
  • White spots

Alternatives to Leaving Your Betta Fish Without Food

Leaving your Betta for a couple of weeks without food and care is not optimal. Check out the following list of alternatives that may work for you.

Betta Sitter

Do you have a family member, friend, or neighbor that may be willing to check in on your Betta? This is ideal. If your Betta is in a 5 gallon (and under) setup, you may also consider bringing your fish to the sitter for convenience. 

Either way, be sure to leave individual servings of food (pre-measured in baggies or disposable cups) so your sitter just has to dump the food into the tank. People that are not used to caring for fish tend to overfeed which can be detrimental to both the water conditions and the Betta itself.

If you are going for a couple of weeks, it will be beneficial to your Betta to show the sitter how to change the water in the tank. Write step-by-step detailed instructions on how to perform this task to ensure the health of your fish.

Automatic Feeder

If your Betta is in a 10-gallon or more tank, then an automatic fish feeder may work for you. These come in several different styles, but they all work on the same principle – you place the premeasured food into the slots and set the timer. The device rotates at the preset time, releasing the food into the tank.

We recommend some careful research into the best one, as some of the inferior models build up condensation on the inside of the slots which clumps the food making it unable to drop into the tank.

For the best results, set up the automatic feeder for a test run before you leave, so you can monitor how it works. 

Block Feeders (Not Ideal)

These types of vacation feeders store food inside a white block that slowly dissolves, releasing food into the tank.

Unfortunately, the food inside these feeders is usually made from a poor-quality, plant-based source that is not healthy for the meat-loving Betta.

In addition, there is no telling at what rate the block will dissolve, so your Betta could have a buffet of food for a couple of days, then be left with nothing for the remaining time you’re away.

Lastly, these blocks have reportedly dirtied the tank water and increased the ammonia levels. 

If you feel this may be your only option, try them out before your planned vacation to see how it reacts in your tank. You will also want to perform water tests to ensure it is not increasing the pH of ammonia in the habitat. 

Small Vases (Not Recommended)

There is a misconception that Bettas can “vacation” in vases containing plants with roots. The idea behind this is the Betta will eat the plant matter and the plant’s in turn will help control the water quality. 

In theory, this is partially true. Yes, the Betta will eat the plants, but as a carnivore, this extended vegetarian diet can create constipation and bloat in your fish. Their stomachs are not designed to break down plant matter and therefore it is not healthy for them to try to do so for days on end.

Secondly, yes the plants can control some water quality, but not where it counts in ammonia and nitrate which will quickly build up, leading to illness or even death of your pet. 

Final Thoughts

Betta fish are one of the few species that can go without food for up to 14 days; however, this is never ideal and should only be done in an emergency.

If you are planning a vacation, then be sure to set your Betta up for success by doing some pre-emptive measures with its tank, getting the proper gear in place, and/or finding a sitter to help with food and water changes. 

Enjoy your vacation knowing your Betta is being taken care of and that it will be happy to see you when you return.