圣珠母丽鱼 · Threespot Eartheater

Overview

Satanoperca daemon is an eartheater with demanding requirements for soft acidic water, fine sand and stable conditions. Frequent availability does not make it easy to maintain. Usually peaceful, it can claim a substantial area when breeding, so plan space around both grouping and parental behavior.

Distribution & habitat

Native waters include Brazil's Negro basin and the Casiquiare and upper Orinoco systems of Venezuela and Colombia. Some reports from elsewhere in Amazonia appear to involve misidentification. Acidic, mineral-poor blackwater is typical. Seasonal connections between rivers and floodplain lakes allow groups to gather and breed in marginal waters with little or no current, over sand, leaves and fallen branches.

Aquarium setup

Provide at least approximately 210 × 60 cm of floor space. Soft sand is essential; coarse particles can hinder feeding, injure gills or be swallowed. Subdued light, wood and roots complete a suitable arrangement. Avoid a heavy leaf layer despite its natural occurrence, since disturbed fragments can clog equipment.

Use a mature system with soft acidic water; untreated tap water is unsuitable in many cases. Ample canister or sump filtration and weekly changes of at least roughly 50–70% support stability. Trap fine particles mechanically while keeping sand out of equipment. Strong filtration capacity should not produce excessive current. Poor upkeep can accompany head and lateral-line erosion or impaired growth.

Diet & feeding

The fish takes mouthfuls of sand and separates edible material, expelling the rest through the mouth and gill openings. Settled individuals also rise for food but continue browsing the bottom between meals. Natural foods include small invertebrates, seeds and detritus. Even large fish need small food particles. Combine fine prepared foods, live or frozen items and some plant-containing food; finely portioned gel mixtures can work. Offer around three to four small meals daily.

Behaviour & compatibility

Outside breeding it is generally gentle and does not prey on fishes longer than a few millimeters. Choose peaceful companions needing similar water, avoiding aggressive bottom dwellers and hard-water species. Nighttime losses have occurred in stingray combinations.

Keep at least five to eight, especially when young. Small groups may concentrate aggression on weaker fish or remain nervous. A social hierarchy is not evidence that isolated housing is preferable.

Sexual dimorphism

Reliable visible differences are usually absent. Gravid females may be deeper-bodied, and their ovipositor becomes visible during spawning.

Breeding

This biparental substrate spawner is seldom bred in aquaria. Raising juveniles together allows natural pairing, with maturity taking at least approximately a year. A pair excavates a large pit, potentially around 2 × 1 meters when space permits, and defends it before spawning. Other conspecifics may require removal.

A cleaned solid surface inside the territory receives repeated batches totaling 200 or more eggs. Leaves, wood or substrate are used to cover them. The female tends most of the clutch while the male guards nearby. Hatching begins after roughly three days; the adults uncover the young, which swim freely approximately 48 hours later. Brine-shrimp nauplii and microworms are suitable then. Both parents usually continue care, although sometimes only the female does so.

Notes

Two dark flank blotches and a conspicuous tail-base eyespot aid recognition. Consider blotch count and reproductive strategy when distinguishing related eartheaters rather than assuming that all are mouthbrooders.