How many Angelfish in a 40-gallon tank?

In this post, we will discuss the topic “How many Angelfish in a 40-gallon tank” and all steps of setting up an Angelfish aquarium. We will also suggest some fish species that are good Angelfish tank mates in community tanks. 

How many Angelfish in a 40-gallon tank?

A 40-gallon tank can fit 2-4 fully grown Angelfish. They will have sufficient room to hide and determine their territory. A 40-gallon tank allows you to have some pretty good community combinations with Angelfish. 

What you should know about Angelfish

Angelfish are marvellous freshwater semi-aggressive fish. However, they stay pacific most of the time. Their body shape and designs fascinate many aquarists. 

They are easy fish to maintain and can be splendid in a community tank, a centrepiece. They usually grow up to 6 inches in length and 10 inches in height. In captivity, Angelfish can live for up to 12 years.

These fish are omnivores. They are usually fed twice a day with some fresh vegetables, live worms and shrimp, freeze-dried items, and some industrialized flakes and pellets.

What are the best tank mates for Angelfish

Although Angelfish are semi-aggressive fish, they can be tankmates to several species in community tanks. It is recommended to stick with peaceful non-aggressive fish that are not fin-nippers, or too small to become prey, or too big to attack the Angelfish. 

Some of the Angelfish tank mates are listed below.

  • Dwarf Gouramis 
  • Albino corydoras 
  • Bronze corydoras 
  • Sterbai corydoras 
  • Adolfoi corydoras 
  • Columbian tetras 
  • Lemon tetras 
  • Rummy nose tetras 
  • Bristlenose plecos 
  • Bolivian rams
  • Kuhli loaches 
  • Swordtails 
  • Platy fish
  • Molly fish
  • German Blue Ram
  • Keyhole cichlids
  • Kribensis cichlids
  • Guppies
  • Head and Tail Light tetras

3 core tips to keep in mind when raising Angelfish

1.   Angelfish’s age

Younger Angelfish tend to be more easy-going and social than adults. Thus, introducing them to new fish while they are still young is a method to diminish aggressive behaviours.

2.   Angelfish’s size

Angelfish are medium-sized fish that grow around 6 inches long and 10 inches tall. Thus, while scheming the stocking combination, it is recommended to always go with the maximum potential size of the fish.

3.   Angelfish’s temperament

Angelfish are semi-aggressive fish. This means they can get hostile sometimes, mainly when they feel threatened, at the entrance of invaders, or while guarding their young. Aggressive behaviour is a strong sign that some of the fish should be moved into another tank or that you should get a bigger tank.

Angelfish tank tips

Angelfish are originally from tropical slow-moving waters of the Amazon River basin. Thus, tank and water settings must be similar to their natural environment, tranquil and warm well-planted tanks.

Water parameters

Quality of water is a very important condition to guarantee. It is important to make sure the tank is free from contaminants and diseases. The temperature range should be from 78 to 84 and pH levels from 6 to 8. Angelfish requirements for water hardness are between 3 and 8 dKH. 

Tank size

Angelfish are medium-sized semi-aggressive territorial fish that inhabit heavily-plated water bodies. Accordingly, they require more space than the general rule “1 inch of fish per gallon” states.

Moreover, they are not shoaling fish. However, they enjoy better being in small groups better than being alone, as they feel more secure in the companion of equals. A 40-gallon tank can house 2-4 fully grown Angelfish. 

Besides the Angelfish size, there are also some other explanations for them not to obey the usual rule “1 inch of fish per gallon”:

1.   Decorations: Angelfish require lots of decorations, as well as live plants. These features occupy space, and thus, this should be taken into account when calculating Angelfish space requirements. 

2.   Smaller tanks are more demanding: Angelfish need renovated water constantly. Thus, having smaller tanks will require changing the water more frequently.

3.   Territorial fish: Angelfish are territorial fish. Therefore, they need enough room to establish their territory.

4.   Easier cleaning: Bigger tanks demand less effort when cleaning, as this would happen with greater interval than with smaller tanks.

Water filtration system

The filtration system is very important to keep high-quality water and avoid contaminants and diseases. Thus, having a suitable filtration arrangement is strongly recommended. For a 40-gallon tank, it is also suggested to run 15 % water changes biweekly. 

Plants and Substrate

Angelfish enjoy heavily-planted aquariums with fine sandy substrate. Therefore, it is recommended to have live plants like Java moss, Java fern, Acharis, or Amazon sword in your tank, as they will resemble the Angelfish natural habitat.

Additionally, it is also important to set some hiding spots in the tank. The Angelfish will feel safer and the plants will help you with water quality conservation.

40-gallon tank dimensions

A standard 40-gallon tank dimension is 36 x 13 x 20 inches. However, it is likely to find many other arrangements and dimensions. The tank’s general weight when filled is around 455 lbs.

40-gallon community tank combinations

A 40-gallon tank also makes it possible to build a community tank. Here are some combinations with Angelfish for a 40-gallon community tank.

–       4 Peppered corys + 6 Head and Tail Light tetras + 6 Cherry Barbs + 6 Harlequin rasboras + 1 Angelfish + 1 Sparkling Gourami + 3 Platies;

–        6 Kuhli loaches + 6 Peppered corys + +1 Angelfish + 6 otos + 8 Lemon tetras.

Tips for a 40-gallon tank

–       Set a routine of water change – 15% of water per week

–       Good filtration and heating systems;

–       Avoid overpopulation and overfeeding;

–       Consider fish species requirements and behaviours;

–      Plants, substrate and décor also take space in a tank.


In this post, we discussed “How many angelfish in a 40-gallon tank” and all steps of setting up an Angelfish aquarium. We also suggested some fish species that are good Angelfish tank mates in community tanks.

If you have any thoughts or doubts, feel free to drop us in a comment below!

Frequently Asked Questions (FAQs): How many Angelfish in a 40-gallon tank

How many Angelfish can you put in a 40-gallon tank?

It is possible to keep 2-4 Angelfish in a 40-gallon tank. It is important also to consider the size and temperament of each individual. When fully grown, they can become more territorial and aggressive and thus, they will require more space or even split into other tanks.

How big of a tank is it needed for 2 Angelfish?

A pair of Angelfish requires a minimum tank size of 29-gallon. Thus, there will be enough room to set the fish, the substrate, plants, and equipment. 

Are Angelfish OK alone?

Although they prefer being kept in groups, they do well alone in a tank with plenty of space, plants, and some tankmates.

What is the lifespan of an Angelfish?

Angelfish usually live for up to 10-12 years. Although, there are some records for 15 years old Angelfish.

Can I keep 2 male Angelfish together?

It is possible to keep 2 male Angelfish in the same tank. However, they are recommended to be introduced while young as their territorial behaviour is weaker.

What Barbs are peaceful?

Some peaceful Barb species are Cherry, Gold, Checkerboard, and Pentazona barbs. They are good community tank mates and their colour patterns are amazing.


How Many Angelfish In A 40-Gallon Tank? Will They School? 2021.

Angelfish Care Guide.

Angelfish Complete Care Guide, Size, Life Span, Tank Mates, Breeding. 2020.

Jason. 2017. 15 Great Angelfish Tank Mates (Complete Compatibility Guide).

How Many Angelfish Should Be Kept Together?

How many Angelfish? 3 Methods for Calculating How Many Angelfish You Can Put in Your Aquarium. 2012.