Green Sunfish

Lepomis cyanellus is one of the most widespread and adaptable sunfishes in North America, tolerating turbid, warm, or low-oxygen water that other species cannot endure. Its large mouth relative to body size hints at its predatory appetite — it eagerly takes fish, insects, crayfish, and worms. Breeding males develop vivid turquoise speckles and an intense blue-green wash across the flanks.

In the aquarium, Green Sunfish are bold and interactive but can be notoriously aggressive, especially as they mature. A single specimen in a large, well-decorated tank with robust tankmates is the safest approach. They adapt readily to a variety of foods and are among the easiest native fish to acclimate to prepared diets.

Given their hardiness and willingness to feed, they make excellent entry-level native fish for keepers transitioning from tropical species, though their aggression demands respect. Adequate territory and hiding spots for all inhabitants are essential to reducing conflict.

Water: 10–28 °C, pH 6.5–8.0, tolerates a wide range of hardness and moderate turbidity. Tank: 300 L minimum; sturdy décor — rocks and driftwood; avoid delicate plants. Feeding: Live/frozen invertebrates, earthworms, feeder insects; accepts pellets readily. Breeding: Nest-builder in gravel; male aggressively guards nest — provide hiding spots for female. Compatibility: Keep singly or with large robust fish; will consume anything that fits in its mouth.