7 Large Fish for a Planted Tank

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Few things are exhilarating as crafting a larger aquatic setup for large and imposing fish. This takes work, careful planning, substantial finances, and some serious logistical work. But what are the best large fish species to use for your massive planted aquarium?

For the record, by massive, we mean 75 and 125 gallons or more, based on your expectations. We have 7 fish species to consider in this sense:

1. Angelfish

While this isn’t exactly among the largest tank fish you can get, the Angelfish can reach respectable sizes. The average size of an Angelfish revolves around 7 inches in length and around 13 inches in height, thanks to its impressive dorsal fin.

These fish can live up to 12 years in captivity when provided ideal living conditions and a balanced diet. Most importantly, a 75-gallon tank will provide you with sufficient space for a proper Angelfish shoal. These fish get along well with one another, so long as they don’t have to compete for food, space, females, or anything else worth pursuing.

Environmental Requirements

The ideal temperature revolves around 78 to 86 °F, with the goldilocks zone resting in the upper 70s. You should increase the temperature to around 82-84 during the mating season or when fry are present in the environment.

Angelfish are pretty easy-going in terms of space requirements. You don’t need more than 30 gallons for 2 pairs which means that a 75-gallon tank will accommodate at least 10 Angelfish.

This fish also requires a peaceful and clean habitat and a nutritious diet to thrive. They are hardy fish, so slight fluctuations in their water parameters won’t disturb them too much unless they get extreme. A planted aquarium is ideal for Angelfish since it boosts oxygenation and keeps them calmer and more docile.

Temperament and Personality

Angelfish are rather friendly fish towards one another and towards other tankmates. That said, you should be wary about their potential tankmates. Angelfish have large and ‘fluffy’ fins, so pairing them with fin nippers is generally a bad idea.

These will stress out the Angelfish, forcing them into hiding and affecting their overall health. They also risk causing microinjuries which can result in localized infections with potentially deadly outcomes.

Angelfish are also slow eaters and swimmers. Pairing them with more energetic species may stress the Angelfish and even cause them to starve if they can’t keep up with their tankmates during mealtime.

One final point – Avoid extreme size differences. If the Angelfish’s tankmates are too small, the Angelfish might see them as food. If they’re too large, they may attack or bully the Angelfish. The ideal tankmates should be close in size and display a more laid-back, friendly behavior, matching that of the Angelfish.

Interesting Facts

It can be difficult to differentiate between males and females, making the mating process that much more difficult. Inexperienced aquarists often run into the problem of sexing their Angelfish, which can lead to having multiple specimens of the same sex in the tank.

This isn’t a problem for female-only populations, but it is one for male-only ones. Males tend to grow more aggressive and competitive towards one another.

So, always learn about sexing your Angelfish properly before deciding which to get and how many you can handle.

By the way, the Angelfish female will produce approximately 1,000 eggs in one spawn, which can result in around 400-600 fry. Not all of them will survive, but many will. So, be ready with a nursing tank if you want to separate the fry from the main population.

2. Rainbowfish

The rainbowfish is an interesting entry because it describes a group of fish that vary wildly between one another. More than 50 types of rainbowfish are available, each displaying astounding differences, including in size, coloring, pattern, and behavior.

So, expect your rainbowfish to vary in size between 1.5 (the threadfin rainbowfish) and 8 inches (Melanotaenia bosemani or Boseman’s rainbowfish), depending on which species you’re going for.

These fish are omnivorous and peaceful and can live up to 12 years with proper care. However, most rainbowfish species only come with lifespans between 5 and 8 years.

Environmental Requirements

The rainbowfish likes the company of its own. This is a schooling species, meaning that the fish spend most of their time in a school, swimming in tandem to protect themselves from predators. So, consider a tank size of at least 30 gallons for a school of 5-6 specimens.

Naturally, this depends on the fish’s size. Larger rainbows may require double that. A 75-100-gallon environment should be more than enough for a rich rainbowfish school.

The ideal temperature for them is 74-80 °F with a pH value of 6.4 to 8.0 and water hardness up to 20 dGH. These fish are easy to keep since they are adaptable and less pretentious than others. Live plants are necessary to emulate the fish’s natural environment and provide the fish with a safer and lusher habitat.

Temperament and Personality

The rainbowfish is peaceful and friendly and will get along with most tankmates. Make sure that there’s enough space for everyone and choose their tankmates carefully. Despite the rainbowfish being quite sociable and friendly, this is also an energetic and avid swimmer.

This will cause the rainbowfish to swim fast and eat even faster, creating an environment with fierce food competition. Slower species will have difficulties getting their full of nutrients.

Interesting Facts

It’s better to keep rainbowfish in schools of at least 6 specimens. This provides them with an improved sense of security, making the fish appear more energetic and positive. Keeping rainbowfish alone will cause them to stress out and appear more lethargic and withdrawn.

This is an important mention because rainbowfish are known to jump out of the tank when stressed or threatened. A school will calm them considerably since they can rely on the presence of other fish to face any perceived threats.

It’s also worth noting that rainbowfish are prone to some health problems like fin rot and Ich. So, you should provide them with a clean and healthy environment to keep them safe.

3. Sunfish

The sunfish is that type of creature that bamboozles novice and veteran aquarists alike. If you’ve never heard of this species before, typing its name in Google will get you nowhere. And by ‘nowhere,’ I mean it will take you to the Ocean sunfish, which can weigh up to 2.5 tons. This isn’t something you can cram up in your home tank.

Fortunately, today we will discuss about the freshwater sunfish which is way more manageable. There are multiple species of freshwater sunfish available, but we will discuss about the larger ones like the Bluegills. These can grow up to 16 inches, require a lot of space, and display a long, predator-like body.

They are somewhat similar in appearance to cichlids.

Environmental Requirements

Bluegill sunfish are some unique specimens with astounding resilience and hardiness. They prefer water temperatures between 65 and 80 but can easily withstand far greater values.

It’s been reported that many bluegill sunfish can survive in temperatures as high as 95 °F and as low as 50 or lower. Obviously, you shouldn’t test the fish’s limits since those temperatures are far from ideal. But they stand proof of the fish’s incredible resilience.

Other than that, all environmental conditions are standard. Medium lighting, a 6.0-8.0 pH range, and clean and fresh waters are necessary to keep the sunfish in good health. Be wary, the sunfish may have different environmental requirements, depending on the species itself.

Temperament and Personality

The sunfish is generally calm and will keep to itself for the most part. It won’t interact aggressively with other fish unless you pair them with small species that the sunfish could view as prey. That being said, sunfish males are generally incompatible with each other.

They will fight over food, territory, and females and will often showcase extreme violence. You should only have one male and 2-3 females at most, provided you have the space for them, of course.

Interesting Facts

Sunfish are relatively easy to breed in captivity, provided you ensure optimal conditions. The interesting part, though, is the fish’s breeding proficiency. The sunfish is capable of producing up to 60,000 eggs in one spawn, resulting in thousands of fry.

So, if you’re looking to breed this one, be ready.

4. Kissing Gouramis

The kissing gourami is among the most recognizable fish species in the aquarium world. And one with the most fitting name you could find. This fish is pink with little color variations and displays bulgy lips, stuck in a kissing demeanor. We’ll discuss what those are for later on.

Expect your kissing gourami to grow up to 12 inches, although some specimens can get larger with proper care and good genetics. The average lifespan of a kissing gourami is around 7-8 years, but many reports place the maximum lifespan at around 25 years.

Environmental Requirements

Go for temperature values between 72 and 82 °F. These are standard values for tropical fish and will serve the gourami well moving forward. The other environmental values are also rather typical for tropical fish, including the pH, resting at 6.0 to 8.0, and water hardness at 20 dGH.

These are large and energetic fish, so you need around 50-75 gallons of water to make them comfortable. They are used to slow-moving waters and heavily planted environments, providing them with safety and comfort.

Temperament and Personality

The kissing gourami isn’t too aggressive, but it isn’t the friendliest and most peaceful fish out there, either. Males are quite territorial and violent towards each other, and they may also exhibit bullying tactics towards other tankmates.

Males, in particular, display the interesting behavior of bumping or rubbing against other fish constantly. Not all males will do that, but only the more territorial and aggressive ones. This behavior is believed to relate to the fish’s territorial tendency, as the gourami uses physicality to impose its demeanor.

This can hurt the victims, as the gourami can strip away their slime coat and even cause skin damages. These will get infected fast because the tank water is always filled with bacteria and viruses. You should remove the gourami from the environment if you notice this behavior.

Interesting Facts

Male gouramis kiss each other. However, don’t mistake this behavior for an expression of love, since it’s anything but. The kissing behavior relates more to the fish’s territorial aggression than its predilection towards love. So, if you notice your gouramis making out, know that they’re actually battling for dominance.

Another important aspect is that the kissing gourami is a labyrinth fish. Bettas also fall into this category. They’re called that way, thanks to their labyrinth organ located near the gills. Labyrinth fish use this organ for breathing atmospheric air, which is a useful asset when living in murky, poorly-oxygenated waters. So, make sure that your kissing gourami has easy access to the water’s surface.

Most importantly, keep the fish’s water clean and fresh, despite the animal being capable of surviving in dirty waters. After all, you want your gouramis to thrive, not merely survive.

5. Bala Shark

The Bala shark is only a shark by name. In reality, it belongs to the Cyprinidae family, which makes it a carp, just like the goldfish. Its name comes from its shark-like appearance, with the overgrown sharky dorsal fin that gives it its trademark predatorial look. That being said, this isn’t a predator in the true sense of the word, but an omnivorous fish that will mostly feed on anything it can find.

However, it does show a predilection towards small crustaceans and fish lurking around their habitat.

Bala sharks can grow up to 14 inches and will live around 10 years in captivity. It’s uncertain how long it can live in the wild, given that Bala sharks are considered endangered and protected.

Environmental Requirements

This is a social fish, so it requires the presence of its own kind to remain calm and peaceful. So, consider at least 120 gallons of water for a group of 4-6 sharks. The ideal temperature rests around 72-82 F, although the fish can withstand some variations occasionally. Water hardness is best kept under 10 dGH.

Ideally, water temperature should remain stable because Bala sharks are sensitive to temperature changes. They are more prone to white spot disease in cold waters (below 65 °F.)

Temperament and Personality

Bala sharks are generally peaceful, especially as juveniles. The adults, however, will get a taste for eating smaller fish. So, you should never pair them with fish that qualify as prey for them. This includes anything below 3 inches, along with any type of crustacean.

Bala sharks are also active swimmers, so they may startle slower-moving fish. The ideal tankmates are active, vigorous, and similar in size to prevent bullying or attacks.

Interesting Facts

Bala sharks don’t reproduce in captivity. Or, at least, you cannot breed them. Professional breeders have special conditions in place to help the fish breed successfully. This includes the use of hormones to trigger the fish’s breeding behavior. So, it’s safe to say that we have no idea how the fish breeds by itself in the wild.

It’s also noteworthy that sexing the fish is next to impossible. There are no clear differences between males and females, except when near spawning, when the female’s belly becomes larger.

6. Clown Loaches

This is a highly recognizable fish species thanks to its distinct coloring and cheerful attitude. The clown loach is active and energetic during the day and will spend most of its time darting through its habitat. It is inquisitive, generally peaceful, and prefers to live in larger shoals.

Expect your loach to grow close to 12 inches or more in the ideal conditions. This means that a school of 4-8 individuals will require quite a lot of space. Even more interesting, clown loaches can live up to 25 years with optimal care. However, most specimens will reach around half that.

Environmental Requirements

This is a carnivorous bottom lurker that demands a lot of space. A properly established school of loaches needs at least 100 gallons to thrive. The optimal temperature rests between 75 and 85 °F with a pH of up to 7.5 and water hardness of 15 dGH at most.

Make sure to provide a variety of hiding areas, including rocks, tunnels, and crevices, especially if the light is too bright. These fish prefer low-light conditions since it helps them feel safer. You should also use sturdy live plants since these are active fish that can damage the plants during their daily activity.

Temperament and Personality

Clown loaches are typically friendly, especially when kept in larger groups. Sufficient space is necessary to prevent territorial fights because males can be rather difficult towards one another. And because these loaches are energy-filled, so they require a vaster playing ground.

Since this is a carnivorous fish, make sure its tankmates are close in size. Otherwise, the loach will see them as prey with obvious consequences.

Interesting Facts

Clown loaches are notoriusly difficult to breed in captivity. This is mostly due to the males’ behavior since they tend to eat the eggs soon after spawning. It’s unclear why they do that in captivity but not in the wild.

So, whenever you’re getting a clown loach, the fish most likely comes straight from the wild. Or, at best, from a fish farm or a professional breeder with vast experience in breeding them.

7. Red-Bellied Piranha

I simply could not close out this list without adding a piranha as a final entry. The red-bellied piranha is every aquarist’s dream, provided we’re talking about people who love omnivorous predators. This is among the most recognizable and mean-looking piranha species. The fish is silver-grey with splashes of red covering the belly and the pectoral and anal fins.

The red-bellied piranha can grow approximately 8-10 inches in captivity and up to 12-14 inches in the wild.

Environmental Requirements

This piranha requires approximately 40 gallons of water per specimen. This may sound excessive, but it’s necessary to keep the fish healthy and happy. The ideal temperature sits at around 74-82 °F with a water hardness of up to 20 dGH.

Given that one fish requires around 40 gallons of space and that you’re aiming for a 125-gallon tank at most, keeping the piranha in a school is unrealistic. I’ve mentioned this because red-bellied piranhas typically live in schools of 20-30 individuals in the wild, allowing them to become a true force of nature in their habitat.

Temperament and Personality

This is where things get spicy. Red-bellied piranhas are extremely aggressive, but this is pretty much a given at this point. They are territorial, violent, and predatorial in nature, capable of killing and devouring a variety of fish species. Including ones similar in size.

Finding reliable tankmates for these fish may be difficult, as they will either bully or straight-up kill anything lurking in their tank. Large semi-aggressive cichlids can make for decent tankmates since piranhas won’t see them as potential prey.

Other potential tankmates include guppies, danios, mollies, and other small and cheap fish, provided they have a variety of hiding spots to retreat to. These list among the piranhas’ meal list, but they’re also fast and fidgety enough to escape any impending danger. Just make sure that they have a variety of plants, rocks, and tank decorations to retreat to when threatened.

And don’t invest in more expensive specimens, since some of them will fall prey to the aggressive piranhas, no matter how much you’d try to prevent that.

Interesting Facts

Interestingly enough, piranha males exhibit a well-evolved parental instinct. They will allow the female to lay the eggs, fertilize them, then take on the task to protect them from intruders.

The resulting fry, however, will display cannibalistic tendencies and will eat each other. This allows the piranha fry to achieve 2 things: get readily-available nutrients from their siblings and promote the surviving-of-the-fittest rule.

It’s a natural behavior that should only concern you if you’re trying to keep all of the fry. In that case, you should relocate the fry into a larger tank with a variety of hiding areas to minimize their cannibalistic interactions and tendencies.


I’m sure you can find an array of different large fish species to use for your 100+ gallon tank. But you can’t deny that today’s list offers quite some colorful options.

Whether you’re going for a gentle and peaceful angelfish or a monster like the red-bellied piranha, you now have a wider selection pool to consider. So, you’re welcome!

Author Image Fabian
I’m Fabian, aquarium fish breeder and founder of this website. I’ve been keeping fish, since I was a kid. On this blog, I share a lot of information about the aquarium hobby and various fish species that I like. Please leave a comment if you have any question.
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