A strikingly beautiful North American native fish often likened to a cold-water cichlid. Known for their brilliant blue and orange coloration and elongated opercular flaps ('ears'). They are highly territorial, predatory, and require a large, unheated or cool-water aquarium with plenty of structure.
Longear Sunfish At a Glance
Longear Sunfish Tank Requirements
Will Longear Sunfish fit in your tank?
Care guides tell you what Longear Sunfish needs, the next question is whether your tank can safely provide it. Test Longear Sunfish against your tank size, maintenance needs, and the fish you already keep before you buy.
Longear Sunfish Water Parameters
Longear Sunfish Temperament & Compatibility
Longear Sunfish Varieties
Each variety inherits the species defaults above. Only differences are highlighted.
Male
Males boast spectacular iridescent blue spotting, bright orange/red bellies, and distinctly elongated black opercular 'ear' flaps. They are highly territorial, especially when building and guarding spawning nests in the sand.
Differs in 1 trait from base species
Also known as: Show Male, Breeding Male
Female
Females are significantly duller, typically olive-brown with faint spotting, and have much shorter ear flaps. They are slightly smaller and less territorial than males, though still highly predatory towards smaller fish.
Differs in 3 traits from base species
Also known as: Female Sunfish
Longear Sunfish Care Guide Summary
The Longear Sunfish, scientifically known as Lepomis megalotis, belongs to the Other family group. Adults reach a maximum size of approximately 18 cm and have a compressed body shape with a moderate growth rate. Classified as aggressive, this species primarily occupies the mid-level and bottom zones of the aquarium and produces a high level of biological waste.
To thrive, the Longear Sunfish requires a freshwater only aquarium with a minimum volume of 208 litres and a tank length of at least 120 cm. Water temperature should be maintained between 10°C and 25°C, with a pH range of 6.5–8.5 and a general hardness of 8–20 dGH. A moderate water flow is preferred.
Due to its specialist needs, the Longear Sunfish is best suited for fishkeepers who can provide a carefully planned setup. This species is available in 2 varieties: Male and Female. Each may differ slightly in size, temperament, or care needs, so it is worth checking the specific requirements of the variety you plan to keep.
Longear Sunfish Habitat Setup
When setting up an aquarium for the Longear Sunfish, a moderate water flow best suits their natural preferences. Because this species occupies the mid-level and bottom zones, the aquarium layout should prioritise open swimming space in the centre of the tank for free movement and sufficient floor space with hiding spots among rocks, wood, or dense planting. Useful additions include a sand substrate to accommodate their sifting behaviour, smooth gravel or rounded substrate to protect their sensitive barbels, and driftwood, which can serve as both a hiding place and a dietary supplement. Keepers should note that expect substrate disturbance, so lightweight décor should be secured.
Longear Sunfish Compatibility Notes
Classified as aggressive, the Longear Sunfish is best housed alone, as they do not tolerate others of their kind in confined spaces. When choosing tankmates, any fish small enough to fit in its mouth will likely be eaten, conspecific aggression can be intense, especially in smaller tanks, and territorial behaviour may cause issues if hiding spots or floor space are limited. Selecting tankmates that favour different water layers from the mid-level and bottom zones can help reduce competition and territorial overlap.
Who Longear Sunfish Is Actually For
Longear Sunfish is best for a fishkeeper who expects a species with attitude and plans the tank around that behavior and can provide someone who understands its individual space requirements. It makes the most sense for a hobbyist who will actually build around its needs, especially sand.
The most common mistake is treating Longear Sunfish like any other community fish and skipping the soft sand it needs to forage safely. Another frequent problem is forcing it into an over-busy community when it would do better with more room or more deliberate tankmate choices.
Longear Sunfish Recommended Tank Sizes
Standard aquarium sizes that meet the minimum volume and length requirements for Longear Sunfish.
55 Gallon Standard
60 Gallon Breeder
75 Gallon Standard
90 Gallon Standard
125 Gallon Standard
150 Gallon High
Frequently Asked Questions About Longear Sunfish
How big does Longear Sunfish get?
Longear Sunfish (Lepomis megalotis) typically reaches a maximum adult size of approximately 18 cm. They have a compressed body shape and a moderate growth rate.
What tank size does Longear Sunfish need?
A minimum aquarium volume of 208 litres and a tank length of at least 120 cm are recommended for Longear Sunfish. This ensures enough swimming space and helps maintain stable water conditions.
What water parameters does Longear Sunfish need?
Longear Sunfish thrives in freshwater only conditions with a temperature range of 10–25°C, a pH between 6.5 and 8.5, and a general hardness of 8–20 dGH. A moderate water flow is preferred.
Is Longear Sunfish peaceful or aggressive?
Longear Sunfish is classified as aggressive with an aggression score of 7 out of 10. Careful tankmate selection is essential to avoid conflict.
Can Longear Sunfish live with others of its kind?
No. Only one Longear Sunfish should be kept per tank. Keeping multiples in the same aquarium typically results in aggression and stress.
Does Longear Sunfish have any special tank requirements?
Yes. Longear Sunfish benefits from sand (sifters), smooth gravel (sensitive barbels), and driftwood (digestion/hiding) in the aquarium. These features help replicate their natural habitat and promote overall health and well-being.
Useful setup supplies
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Guidarium Editorial Desk
Reviewed against Guidarium care, stocking, and compatibility standards. Read the editorial policy.
- Last reviewed
- May 11, 2026
- Last updated
- May 11, 2026
- Issues or corrections?
- Contact the editorial team
Plants That Suit Longear Sunfish
These plants pair well with Longear Sunfish based on shared water preferences, layout fit, and how likely they are to hold up in the same aquarium.
Afzel's Anubias
Anubias afzelii
Anubias Barteri
Anubias barteri
Belinda's Buce
Bucephalandra belindae
Buce Motleyana
Bucephalandra motleyana
Congo Anubias
Anubias heterophylla
Crepidomanes Fern
Crepidomanes auriculatum
Fish Similar to Longear Sunfish
Redbreast Sunfish
Lepomis auritus
A colorful, North American native freshwater fish known for its bright orange-red belly and an elongated, solid black opercular flap ('ear'). As a temperate species, they thrive in unheated aquariums. They are aggressive, territorial predators that will dig nests in the substrate and consume any tank mate small enough to fit in their mouths.
Bluegill Sunfish
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A highly active and intelligent North American native fish. Known for their deep, laterally compressed bodies and the distinctive dark spot at the base of the dorsal fin. They are predatory and territorial, often treated as 'coldwater cichlids' by hobbyists. Because they grow large and are highly active, they require significant swimming space and heavy filtration.
Pumpkinseed
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A robust North American native fish commonly known as the 'Shellcracker' due to its specialized pharyngeal teeth used to crush snails and mollusks. They are a temperate (coldwater) species that makes an excellent subject for a large native unheated aquarium. They are semi-aggressive, territorial, and will consume any tank mate small enough to fit in their mouths.
Orangespotted Sunfish
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