Angelfish — Elegant “Angels” of Your Aquarium
Angelfish (Pterophyllum scalare, Lichtenstein, 1823) are among the most iconic and recognizable freshwater aquarium fish in the world. Belonging to the family Cichlidae, they are native to the slow-moving and still waters of South America — the Amazon, Orinoco, and Essequibo river systems and their tributaries. Alongside the common angelfish P. scalare, the genus includes the altum angelfish (Pterophyllum altum) and Leopold’s angelfish (Pterophyllum leopoldi), though it is P. scalare that forms the basis of virtually all cultivated aquarium varieties.
Their laterally compressed, vertically elongated body is a product of evolution in densely planted environments, allowing effortless movement between stems and leaves. Despite their graceful appearance — which earned them the nickname “angelfish” in European aquarium circles — they are true predators, hunting invertebrate larvae, small crustaceans, and tiny fish from within the vegetation. Their camouflage-inspired coloration helps them blend into their surroundings both in the wild and in a home aquarium.
Angelfish Care: Setting Up the Perfect Tank
Providing conditions that mimic their natural habitat is the cornerstone of successful angelfish care. In the wild, these fish inhabit calm, warm, slightly acidic, and soft waters with abundant plant growth.
Tank Size. The minimum recommended volume for a single pair is 100 litres, but 150–200 litres or more is strongly preferred. Crucially, tank height matters: adult angelfish including fins can reach 25–30 cm vertically, so aim for at least 45–50 cm of water depth. From personal experience, a pair kept in a 250-litre tank with 60 cm depth grew significantly larger and showed more vibrant colours than siblings raised in a standard 100-litre aquarium.
Filtration and Flow. Filtration is essential, but strong currents are stressful for angelfish and can stunt their growth. Use a filter with a spray bar or diffuser to minimise direct flow. Direct the output along the glass rather than across the open water.
Plants and Décor. Dense plantings of echinodorus (Echinodorus spp.), vallisneria (Vallisneria spp.), and cryptocorynes (Cryptocoryne spp.) along the back and side panels provide security and replicate the natural biotope. Leave an open swimming area in the centre. Driftwood and smooth rocks complete the setup.
Water Changes. Regular partial water changes are non-negotiable. Change 20–25% of the tank volume weekly, using dechlorinated water at the same temperature.
Tank Mates. Good companions include calm tetras, corydoras catfish, and plecos. Betta fish are sometimes kept alongside angelfish, but this pairing is not recommended: angelfish can nip the betta’s long, flowing fins, or an aggressive betta may in turn harass the angelfish.
Angelfish (Pterophyllum scalare) Water Parameters Table
| Parameter | Value |
|---|---|
| Water Temperature | 24–28 °C (optimum 26 °C) |
| pH | 6.0–7.5 (optimum 6.5–7.0) |
| Hardness (GH) | 3–15 °dGH |
| Minimum Tank Volume | 100 L (pair), 200+ L (group) |
| Minimum Tank Height | 45–50 cm |
| Lighting | Moderate, 0.3–0.5 W/L |
| Current | Weak or absent |
| Water Changes | 20–25% weekly |
| Adult Body Size | Up to 15 cm length, 25–30 cm height |
| Lifespan | 10–15 years |
| Social Behaviour | Schooling; keep min. 4–6 individuals |
Angelfish Care: Feeding and Diet
Proper nutrition is directly linked to the health, colour intensity, and longevity of angelfish. Like most fish, they lack a satiety mechanism — portion control is entirely the keeper’s responsibility.
Recommended Foods:
– Live and frozen foods: bloodworms (Chironomus spp.), tubifex (Tubifex tubifex), brine shrimp (Artemia salina), daphnia (Daphnia spp.). Live bloodworms should be rinsed thoroughly and ideally quarantined before feeding; frozen is a safer alternative.
– Seafood preparations: finely chopped boiled shrimp or mussels provide excellent protein and micronutrients.
– High-quality dry foods: flakes and granules from reputable brands (Tetra, JBL, Sera) as a dietary staple.
– Vegetable supplements: blanched spinach or spirulina-based foods support immunity.
Feeding Schedule: Feed juveniles 3–4 times daily to support rapid growth. Adults: twice daily (morning and evening), with each meal consumed within 2–3 minutes. Introduce a fasting day once a week to prevent obesity and digestive issues.
Breeding Angelfish
Angelfish are monogamous; an established pair can bond for years. Triggering spawning requires:
- Raise temperature gradually to 28–30 °C (no more than 1–2 °C per day).
- Provide broad-leaved plants — echinodorus, nymphaea, anubias — or a clean ceramic tile or spawning cone.
- Improve water quality: perform several changes with slightly softer, more acidic water (pH 6.5, GH 4–6) in the days before spawning.
- Increase live food in the diet.
The female deposits 150–1,000 eggs in neat rows on the chosen substrate; both parents guard the clutch and fan it with their fins. At 28 °C, eggs hatch in approximately 48–60 hours. Fry become free-swimming after another 5–7 days. Start food: infusoria, newly hatched brine shrimp nauplii, or fine powdered fry food.
Determining sex is difficult before 10–12 months of age. Mature males are slightly larger, display a more pronounced nuchal hump, and have a pointed dorsal fin. Females develop a rounded abdomen before spawning and show a short, broad ovipositor.
If you enjoy exploring other fascinating cichlid species, the chocolate-blue lamprologus is a striking African alternative worth considering. For those looking at broader fish-keeping options, guppies remain one of the best beginner fish, easy to house alongside young angelfish in larger setups.
Common Diseases and Prevention
Angelfish are relatively hardy but can fall ill when conditions are suboptimal:
– Ich (white spot disease) — triggered by temperature drops or stress; treat by raising temperature and using appropriate medication.
– Hexamitosis — a cichlid-specific internal parasite linked to deteriorating water quality.
– Fungal infections — usually secondary, developing on injured tissue.
Prevention is built on stable water parameters, quarantining new fish for at least 2–3 weeks, and a varied, nutritious diet. For in-depth information on fish diseases and treatments, see our article on betta fish diseases — many pathogens and remedies overlap across tropical species.
Authoritative references: Fishbase.org — Pterophyllum scalare; Seriously Fish — Pterophyllum scalare.
FAQ: Angelfish Care — Common Questions
1. How many angelfish can I keep in a 100-litre tank?
One pair is the practical maximum. Adding more fish to a small tank leads to territorial conflicts, especially during spawning. For a group of 4–6, target 200 litres or more.
2. Can angelfish live with neon tetras?
In theory, yes — but adult angelfish frequently treat small neon tetras as food. The safest approach is to introduce tetras when they are already fully grown, or raise both species together from a young age.
3. Why has my angelfish turned dark and stopped eating?
Darkening and appetite loss are classic stress or illness signals. Test the water immediately (ammonia, nitrite, pH, temperature) and inspect the fish for visible symptoms. Common culprits are excessive filter current, aggressive tank mates, or the onset of disease.
4. How do I tell male and female angelfish apart?
Reliable sexing is only possible in sexually mature fish. Males are typically larger with a more pronounced forehead hump (nuchal hump), a pointed dorsal fin, and a thin papilla. Females have a broader, shorter papilla (ovipositor) and a visibly rounded abdomen before spawning.
5. What is the ideal temperature for angelfish?
The sweet spot for long-term maintenance is 26–27 °C. Brief excursions to 24–29 °C are tolerated well, but sustained temperatures outside this range compromise immunity and shorten lifespan.
Last updated: July 10, 2026
