How Many Angelfish In A 29 Gallon Tank?

You can keep two angelfish in a 29-gallon tank according to the following: Angelfish reach an adult size of 8-10 inches high and 6 inches in length. Allow 20 gallons for your first angelfish and 10 gallons for each subsequent angelfish to ensure they have enough room. 

While most people buy their angelfish when they are young and still quite small, angelfish can reach their adult size within a year, and you will need to home them in an appropriately sized tank. These hardy cichlids are very popular in home aquariums, but how much space do they need?

How Many Inches Of Angelfish In A 29 Gallon Tank?

When keeping angelfish, you need to ensure that they have enough space to swim freely and that the tank is large enough to cope with the bioload. In fishkeeping, there’s a rule of thumb that each inch of fish requires a gallon of water, but this is more a general guideline than a rule.

For example, a standard 29-gallon rectangular tank will have dimensions of 30 inches wide, 12 inches deep, and a height of 18 inches. By the inch/gallon rule, you could keep approximately 30 inches of fish in it.

While this works perfectly well if we’re discussing a school of neon tetra—these fish will reach an adult size of 1.5 inches, so by these guidelines, a 29/30 gallon tank will house a school of 20.

When using the inches per gallon guideline, the aim is to keep your tank stocked to only about 70% of its total capacity; this helps to keep the tank more stable and the filters and bacteria not overloaded by the debris and ammonia caused by waste.

With a 70% guideline, we shouldn’t go higher than 14 neon tetras in our example. But what if you’re talking about a much larger fish like angelfish?

Two Black Striped Angelfish

How Many Angelfish Can I Keep In A 29 Gallon Tank?

Most adult angelfish reach 6 inches, but they are very tall, unmistakable fish and have a height of around 8 inches. These fish have a much larger biological profile than tetras and need more space to move freely.

If we used the inch per gallon rule here, we’d be able to keep five angelfish in a 29-gallon tank. If we kept our tank at only 70% capacity, we would have 3 (and a half) fish as the recommended number.

However, this still doesn’t consider their tall, flattened body shape and trailing fins. It also doesn’t take their territorial nature into account. While tetras are schooling fish who like to stick together, angelfish will need more space to allow them to mark out their space.

If you keep too many angelfish in too small a tank, your fish will be highly stressed and miserable. You will also run the risk of some of the fish bullying the others and might have some die off due to stress and ill-health.

With all these factors in mind,  I would not keep more than two adult angelfish in a 29-gallon tank.

How Many Juvenile Angelfish Can I Keep In A 29 Gallon Tank?

When you buy your angelfish, they will normally be juvenile and still quite small, perhaps an inch or two in length. If you have a 29-gallon tank, you might think you can keep four or five juvenile angelfish in it until they are larger.

Keeping them like this is possible, but remember that the adult size will be at least six inches long and six-eight inches in height with their long fins. It won’t take long for your angelfish to reach adult size, and you can expect them to reach maturity in about 8-12 months.

You can keep your juvenile angelfish in a 29-gallon tank for a few months before you will need to transfer them to a larger, more suitable tank. On the other hand, you can transfer some of the angelfish to other tanks and leave two angelfish in the 29-gallon.

If you have several tanks available for later use, buying a group of six young angelfish and keeping them in your 29-gallon for a short time will allow you to see which ones will pair up and should be kept together and which ones are bullies and need their own tanks.

Is It OK To Keep Two Angelfish In A 29-Gallon Tank?

29-gallons is suitable for only two angelfish, as these fish will often become more aggressive and territorial as they age. This aggressive nature is one of the reasons many fishkeepers recommend you don’t keep odd numbers of angelfish.

Although the tank could likely cope with a third angelfish, the third angelfish will probably be harassed and bullied, perhaps even to death. Keeping three angelfish in a 29-gallon tank will be cruel and cause your fish too much stress.

One of the issues with angelfish is that you can’t force a pair, so you might have bought two angelfish hoping they get along, and instead, they are constantly nipping and harassing each other and fighting over territory. In this case, it’s best to rehome one of the angelfish in another tank.

If you’re worried that angelfish should be kept in shoals, this is not an issue that should concern you. Although a large group of angelfish can look particularly striking in a huge tank, they are not schooling fish like tetras or rasboras.

Schooling fish are much happier when kept in large shoals, as they feel protected and safe. But angelfish do not move in shoals, though they may occasionally group together.

Angelfish will be quite content to live in pairs or even an individual in a community tank.

What Are Good Tankmates For Angelfish In A 29 Gallon Tank?

If you’ve decided to keep a pair of angelfish in your 29-gallon tank, you’re likely considering what suitable tankmates you could add.

On the one hand, you can set up the tank so that it remains a single-species tank and only has your angelfish, and set the tank parameters up to be exact for the angelfish.

However, if you prefer to have some other fish in your tank, you’ll want to ensure they are not too small, or the angelfish will eat them.

Keeping fish from similar areas together in a tank is a good idea, as that allows you to maintain tank conditions that suit all the fish.

Don’t overcrowd your tank. It’s better to keep only 2-3 species in appropriate numbers than one kind of many different species

Angelfish tend to stay in the middle zone of the tank and move to the surface to feed. Look to add fish that occupy the lower and upper zones to keep the tank from feeling crowded.

In the wild, angelfish come from the wide, slow-moving rivers of the Amazon basin, so consider other Amazonian species.

Consider adding:

  • Corydoras catfish – these like to be kept in small groups and live on the bottom of your tank
  • Rummy-nose tetras – a schooling fish, slightly larger than neons, so less likely to be eaten
  • Platies – these are hardy livebearers, but be aware the angelfish will eat the fry.


If you have a 29-gallon tank, you’ll be unable to keep more than two angelfish. If you are lucky, the angelfish will pair up, and there will be no problems, but if your angelfish are aggressive and territorial, you might have to split them up.

You can keep one angelfish or a pair in a small community 29-gallon tank, provided you don’t overstock the tank, and the fish all require similar water conditions and are not too small and likely to end up a snack for your angelfish.