尖头珠母丽鱼 · Sharphead Eartheater

Overview

Satanoperca acuticeps differs from many eartheaters in being less exclusively tied to bottom feeding and apparently somewhat adapted to open-water life. It is usually very peaceful outside reproduction but highly sensitive to deteriorating water quality and chemical instability.

Distribution & habitat

Native to the central Brazilian Amazon, it occurs in the main channel and lower tributaries between the Tapajós and Tefé, including the lower Negro and Branco systems. Clear or turbid water is more typical than nutrient-poor, tannin-dark blackwater. Main rivers, smaller tributaries and floodplain lakes provide sandy or muddy bottoms with leaves and submerged branches.

Aquarium setup

Allow at least approximately 180 × 60 cm of floor space. Although less bottom-focused than its relatives, it still needs soft sand. Coarse particles can impede feeding, damage gills or cause internal problems if swallowed. Subdued light, wood and branches make useful furnishings.

Heavy leaf litter is not advisable despite its natural occurrence: feeding fish can suspend decomposing fragments and clog filters or pumps. Use a mature system with ample canister or sump filtration and replace at least roughly 50–70% of the water weekly. Poor maintenance can accompany head and lateral-line erosion or impaired growth.

Diet & feeding

This is an omnivore. Wild foods include aquatic and terrestrial invertebrates, substantial zooplankton and phytoplankton, vegetation and detritus. Even large individuals struggle with large food pieces. Offer fine prepared foods with water fleas, brine shrimp, mosquito larvae and similar items, including plant-rich dry food. Gel mixtures are also useful. Three to four small daily meals suit its browsing pattern.

Behaviour & compatibility

Outside spawning it is tolerant of many appropriate peaceful fishes and does not prey on fish longer than a few millimeters. Avoid strongly territorial bottom dwellers and companions needing much harder or less acidic water. Stingray combinations have produced both successes and nighttime losses and should not be assumed reliably safe.

Keep at least five to eight. A hierarchy develops, and too few fish may result in persistent targeting of weaker individuals or an unsettled group. Juveniles show particularly strong grouping behavior.

Sexual dimorphism

Aquarium observations suggest slightly larger males with longer extensions to the rear dorsal fin, while gravid females become deeper-bodied. These are tendencies rather than reliable absolute differences.

Breeding

Both parents care for a substrate-laid brood, but aquarium reproduction is uncommon. Let juveniles pair naturally and expect at least a year before maturity. Space, nutrition and consistent maintenance matter more than any established single trigger.

The pair digs a large pit. The female deposits batches for the male to fertilize, then a thin layer of sand covers the eggs. She performs most egg care while he defends the surrounding area. Hatching takes two to three days. Both usually continue care afterward, though sometimes the female does so alone. Free-swimming fry accept brine-shrimp nauplii and microworms.

Notes

Three dark flank blotches distinguish this fish from the two of Satanoperca daemon and the single blotch of some related fish. It spawns on a substrate; mouthbrooding in other members of the genus should not be generalized to it.