Betta Fish

How Big Do Bettas Get? 3 inches!

4 min read

When you go shopping for Betta Fish, you will probably find a lot of them in tiny bags or cups. You probably wonder how big do bettas get. Here is what I have discovered:

The average full-grown betta fish is 2 – 2.25 inches. Occasionally a betta fish will grow up to 3 inches in length. Their growth is based on how much space they have, water quality, and proper diet. There is also a group of betta fish called, ‘giant betta fish’ that can grow up to 5 inches with the same proper care as a normal betta fish.

When you first see your Betta Fish in the store, it will be close to full-grown. It should be at least close to two inches already.

The reason for this is because bettas are marketed for their bright and elegant colors which are more evident if they are grown.

Your betta will probably grow more after you bring it home but not much. If it is kept too long in the tiny cup or bag that you see it in the store its growth could possibly be inhibited.

how big do betta fish get

How Do I Make My Betta Fish Grow Bigger?

To maximize your betta fishes growth you need three things:

  1. Space
  2. Water Quality
  3. Proper Diet


You may see a lot of info online about keeping betta fish in nano tanks or 2.5 tanks but if you want your betta fish to grow to their full potential, then you need at least 5 gallons for each betta fish but the more space the better.

If you have more space, it gives your betta fish more room to swim around and explore.

You also have more room for toys and tank decorations that your betta fish can swim around and explore.

Water Quality

You should have a filter system with biological, chemical, and mechanical filtration to keep the ammonia out of your betta fish tank.

If too much ammonia gets in your betta fish tank, it could cause health issues and also inhibit their full growth potential.

Get a water testing kit so you can check your betta’s water quality before you change it.

Change at least 20 percent of your betta’s water once a week and 50 percent of your betta’s water once a week depending on the water test results. If the water consistently tests good then you may not need to do the 50 percent water change each month.

You should also have a water heater because betta fish come from tropical waters where it is very warm. Their water temperature needs to be between 75-81 degrees Fahrenheit.

Proper Diet

If your betta fish are not fed properly, this could also inhibit their growth potential.

Betta Fish are carnivores so they eat meat. In the wild, they eat worms, daphnia, bloodworms, brine shrimp, mosquito larvae, and other fish. You should be able to get all of these foods to feed your betta fish online or at your local pet store.

For the aquarium, there are plenty of fish flakes made for betta fish that make a well-rounded and easy diet. You can feed them fish flakes plus some of the other foods that they eat in the wild as treats.

How Quickly Do Betta Fish Grow?

After betta fish hatch from their eggs, they grow to 1.9 inches by the time they are 11 weeks old. In only seven months, a betta fish has full-grown fins that will make your betta seem between 3-4 inches long although some of this length is from their fins and not their body since betta fish only grow between 2-2.25 inches.

Baby betta fish grow so fast, they will begin to eat bigger foods within a few days of birth.

How Big Is A Full-Grown Betta Fish?

A full-grown betta fish is between 2-2.25 inches although some betta fish can reach 3 inches if properly cared for. Their length is measured by their body and not their fins.

How Big Do Bettas Get In The Wild?

Bettas grow about the same size in the wild but the normal range is between 2-3 inches with more 3-inch betta fish than in aquariums, although wild betta fish grow shorter fins and have duller colors.

How Big Do Female Bettas Get?

Female betta fish are a little bit smaller than male betta fish. Female betta fish only grow to 2.5 inches which is as big as the average betta fish gets. Male betta fish are the ones that can grow up to 3 inches. Female betta fish also have smaller fins, which makes them appear smaller than the average male betta fish.

What Is The Biggest Betta?

There is a group of betta fish called giant betta fish that are from betta splendens, the same group that is considered the normal aquarium betta fish. Giant bettas have been specially bred by breeding the biggest betta fish which previously had been 3 inches but now, giant betta fish can grow to 5 inches.

How Big Do Giant Bettas Get?

Giant bettas can grow up to 5 inches in size.

How Big Do Koi Bettas Get?

Koi betta are so named because they have colors that resemble a koi fish but since they are actually betta splendens, koi betta can only reach a maximum length of 3 inches depending on if they are taken care of properly during their growth stage.

How Big Do Veiltail Bettas Get?

Again, veiltale bettas, like koi bettas are just a different color variation of the betta splendens scientific family so the average veiltale betta grows to 2-2.25 inches with the rare case of one of them growing to three inches.

Final Thoughts

We trust this article has answered your question of ‘how big do bettas get.’ A full-grown betta fish is between 2-2.25 inches although some betta fish can reach 3 inches if properly cared for. Their length is measured by their body and not their fins.

Written by:

Pet Aquariums

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