Blue Marble Angelfish (Pterophyllum scalare)

Common Name

Blue Marble Angel

Origin and Habitat

Blue Marble is a captive-bred line of the wild angelfish Pterophyllum scalare. Wild scalare are found throughout the Amazon basin in Brazil, Peru, and neighboring countries, inhabiting calm tributaries, floodplain lakes, and seasonally flooded forests. Water ranges from very soft, tannin-stained blackwater to clearer, more mineral-rich whitewater. Roots, branches, and tall plants provide vertical cover and natural spawning sites. The distinctive marbled pattern and blue iridescence were developed through selective breeding in aquaria, so Blue Marble angels are tank-raised and well-adapted to home aquarium conditions.

Temperature and Water Conditions

Preferred temperature: 77–82 °F (25–28 °C). Wild pH ranges from mildly acidic to near neutral depending on location. In aquaria, stability is far more important than exact wild parameters (except for dedicated breeding setups). Provide clean, well-filtered water with good oxygenation and gentle surface movement. Leaf litter and botanicals are optional but add comfort when water quality is excellent.

Appearance and Size

The Blue Marble features a striking marbled silver-and-black pattern overlaid with a metallic blue sheen that shimmers across the body and fins. Individual variation is high—some show bold black patches on silver, others finer mottling with more uniform blue coverage. Adults have the classic tall, triangular angelfish shape with long dorsal and anal fins that often develop trailing filaments. Males and females look alike; mature males may develop a slightly broader forehead. Body length reaches about 15 cm (6 in), with total height (including fins) much greater.

Diet in the Wild

Opportunistic micropredators that feed on aquatic insects, small crustaceans, worms, and zooplankton among roots and plants. Juveniles forage in leaf litter and quiet margins.

Feeding in Captivity

Use high-quality cichlid micro-pellets or small granules as the staple diet. Supplement regularly with live and frozen foods such as baby brine shrimp, daphnia, cyclops, and finely chopped blackworms to enhance condition and intensify the blue sheen. Feed small portions once or twice daily so fish feed confidently in midwater. A varied diet supports steady growth and vibrant coloration.

Behavior and Tank Setup

Peaceful to semi-peaceful cichlid that forms strong pair bonds. Best practice is to raise a small group of juveniles to allow natural pairing, then keep established pairs with compatible tankmates.

• Tall aquarium with calm flow
• Fine sand or smooth substrate
• Driftwood and vertical roots
• Broad-leaved plants (e.g., Amazon swords) for cover and spawning sites

Good companions include larger calm tetras, pencilfish, Corydoras, and small gentle plecos. Very small fish may be seen as food by large adults.

Breeding

Pair Formation

Grow out a group of juveniles and let a pair declare itself naturally. Once formed, provide space and visual barriers so the pair can claim a territory without stress.

Spawning Site

Angelfish prefer vertical or slightly inclined surfaces. Offer broad plant leaves, smooth slate, or a removable pre-filter sponge on an intake tube if you plan to move eggs for artificial hatching.

Water and Conditioning

Pairs will spawn in neutral, lightly mineralized water, but many breeders achieve better hatch rates in softer, mildly acidic, very clean water with high oxygen. Condition adults with frequent small servings of live/frozen foods and avoid sudden parameter changes.

Egg and Larval Stages

The female lays neat rows of adhesive eggs while the male fertilizes. Both parents fan and clean the clutch. At 77–82 °F (25–28 °C), eggs typically hatch in a few days; larvae remain as wrigglers until free-swimming, then school tightly around the parents.

Raising Fry

Many Blue Marble pairs become excellent parents with experience. Maintain gentle flow, keep pre-filter sponges clean, and feed newly hatched brine shrimp multiple times daily. If pulling eggs, move the spawning surface to a small hatching tank with gentle aeration. Transition free-swimming fry to brine shrimp plus fine powdered fry food. Because marble and blue traits segregate genetically, expect a range of patterns and blue intensity in the offspring—select keepers that best match your preferred look.

Quick Facts

• Scientific name: Pterophyllum scalare
• Common name: Blue Marble Angel
• Origin: Amazon basin species; Blue Marble is a domestic aquarium line
• Adult size: body length ~15 cm (6 in), much taller with fins
• Temperature: 77–82 °F (25–28 °C) preferred
• Wild pH: mildly acidic to near neutral; stability most important in captivity
• Temperament: peaceful to semi-peaceful, forms strong pairs
• Diet: micropredator; accepts quality prepared foods plus live/frozen supplements
• Breeding: open substrate spawner on leaves or slate, strong parental care once experienced; offspring show variable marbling and blue coverage

Tropical Fish Co. Notes

When the light hits a Blue Marble just right the whole fish flashes electric—a silver-and-ink canvas brushed with blue. Give them height, calm water, and broad leaves, then enjoy the courtship dances, tidy egg rows, and the sight of a confident pair herding a school of tiny fry.