Betta Growth Chart: How To Increase The Fish Size?

Among the best-looking fish available is the Betta, without a doubt. In addition to being lively and vibrant, they also have great personalities.

Even though taking care of these little creatures is not difficult, you might be unsure how to start.

As a novice aquarist, you may wonder: How big will my Betta fish grow? Don’t get yourself stressed!

This article will provide you with the Betta growth chart to know clearly about their development at different stages in their life.

Betta Life Cycle

No matter how experienced they are, aquarists of all levels can enjoy raising their first baby Betta.

Although estimating a fish’s actual growth rate might be challenging, it goes through various phases until it is a fully developed adult.

Below is a general life cycle of Bettas:

Egg Stage

The female bettas in the mating aquarium lay the fertilized eggs on the water’s surface, which marks the beginning of your fish’s life cycle.

These eggs are simple to discover if you check for the bubbling nests they produce on the water’s surface of your aquarium.

Depending on the temperature of the water, it may take 2-3 days for betta fry to hatch when you first notice their egg sacs emerging.

Fry Stage

Betta fry is tiny, resembling tiny shrimp in size. They are particularly vulnerable at this time.

It’s crucial to provide them with lots of hiding spots in the tank so they may consume the yolk sacs undisturbed by other fish or potential predators.

Juvenile Stage

The term “juveniles” refers to the fry after they emerged from the egg sac and started to swim freely.

Approximately two weeks after birth, bettas hit this stage. However, the precise period depends on how big the egg sacs are.

They grow faster throughout this time of life; by two months old, they will be around one inch long.

Adult Stage

When your Bettas are one year old and measure around 3 inches long, they are considered adults.

At this stage, you can distinguish between females and males. If given proper care, these fish have a two-year lifespan.

Betta Growth Chart

After learning about the four stages in the Betta life cycle, it’s time to see their growth chart!

With this simple chart, you’ll be able to track your fish’s progress in size each week accurately and according to age.

Growth Stage Length (inches) Findings
Newborn fry 0.1 There is no sign of the tail.
1-week old 0.2 The tail begins to appear.
2-weeks old 0.25 Now you can see the dorsal fins.
3-weeks old 0.35 You can see most parts of Bettas.
4-weeks old 0.45 Fish vary somewhat in size from one another, often by 0.4 to 0.5 inches.
5-weeks old 0.6
6-weeks old 0.8 Fish now vary in length more amongst each other, from 0.75 to over one inch.
7-weeks old 1.1 Most Bettas should be bigger than one inch after seven weeks.
8-weeks old 1.3 At this stage, length growth is gradual and very variable among species.
9-weeks old 1.5 According to several experts, bettas reach their ninth week of age once the “juvenile” period finishes.

Monitoring your fish’s development from birth may be a very fulfilling experience. Remember that these figures might change based on various factors!

betta size

Do Bettas Expand To Fill Their Tanks As They Grow?

It is a controversial question! Generally speaking, this phenomenon really exists, although that isn’t always the case.

Your Bettas will stop developing at a particular stage before they reach their full-size potential if the aquarium is too tiny for them.

Betta fish won’t necessarily grow significantly, but they may if the environment is much greater than they require.

How long does it take for a Betta to grow full size? They may be grown after seven months old. Yet, it depends on their surroundings and your maintenance.

At that point, you may wonder: How do I know when my Betta is full grown? The flowing fins of adult bettas are beautiful. If your fish shows this trait, it is an adult.

adult betta

How To Increase The Size Of Your Betta Fish?

You may take a few measures to guarantee that your Bettas reach their maximum growth potential. Here are some recommendations:

Tank Size

There is a difference in this situation due to the tank. Some claim that Bettas only require a 2.5-gallon aquarium.

It’s the very minimum, though, and it’s a great way to guarantee that your fish stays tiny.

It is advisable to use a least 5-gallon aquarium capacity if you expect your fish to fulfill their maximum potential and grow up to 3 inches long.

In this instance, bigger is better.


Your pets need the right kind of food to reach their complete growth. They require a substantial quantity of good protein.

Feeding them top-notch and excellent tropical seafood flakes is a wise decision.

You may also use certain freeze-dried products. Everything natural, healthful, and high in protein is good.

Ensure your fish only receives as much food as they can consume in two minutes, three times a day, if you expect them to grow healthy.

Be cautious when overfeeding fish because it might lead to illness and stunt their growth.

If you want to make the food yourself for your pets, you can watch this video:


Another excellent approach to guarantee that your Bettas are healthy and have room for growth is to keep the aquarium clean.

To eliminate pollutants, you should replace 25 percent of the tank water weekly.

Additionally, it’s best to clean the gravel, plants, and other objects in your aquarium a few times monthly.

Besides, having a high-quality filter that performs all three types of filtering is critical.

Keeping the aquarium at suitable parameters is the last step. It also applies to the water’s hardness, temperature, and pH level.

tips for growing betta size

The Bottom Line

After referring to this Betta growth chart, you can easily predict how large your pets will grow at each development step.

Remember that these numbers are only approximate. The exact size of your fish depends on their habitat and your care.

Therefore, giving these creatures proper maintenance is essential to reach their maximum growth potential. Thanks for reading!