Altum Angelfish Care Guide: The Wild Angel That Demands More

Table of Contents

• Key Takeaways
• Species Overview
• Classification
• Origin & Natural Habitat
• Appearance & Identification
• Average Size & Lifespan
• Care Guide
• Tank Mates
• Food & Diet
• Breeding & Reproduction
• Common Health Issues
• Common Mistakes to Avoid
• Where to Buy
• Frequently Asked Questions
• Closing Thoughts
• References

If you’ve ever looked at a common angelfish and thought it was impressive, the altum angelfish will completely reset your expectations. This is the wild angel. The real deal. Standing up to 14 inches tall from fin tip to fin tip, with a steeper forehead profile, more pronounced vertical barring, and a dignified presence that makes the common angelfish look almost plain by comparison, the altum is the angelfish that experienced fishkeepers dream about.

But the altum demands more. Much more. While common angelfish (Pterophyllum scalare) have been captive-bred for generations and can tolerate a wide range of conditions, altum angelfish come primarily from wild-caught stock and require soft, acidic water, warm temperatures, and a level of care that puts them firmly in the advanced category. In my 25+ years in the hobby, I’ve watched many experienced fishkeepers struggle with altums simply because they underestimated how different these fish are from their domestic cousins. This guide will help you understand exactly what you’re getting into.

Key Takeaways

• Not your average angelfish. Altums require soft, acidic water (pH 4.5-6.5) and warm temperatures (78-84°F) that are far more demanding than common angelfish
• Tall tanks are essential. With a total height of up to 14 inches including fins, altums need aquariums with significant vertical space
• Mostly wild-caught. Captive breeding of altums is rare and challenging, meaning most available fish are imported from Colombia and Venezuela
• Peaceful but sensitive. Altums stress easily and need calm tank mates, subdued lighting, and minimal disturbance
• A 55-gallon minimum for a small group, though 75+ gallons is strongly recommended for long-term success

Species Overview

Field	Details
Scientific Name	Pterophyllum altum
Common Names	Altum Angelfish, Altum Angel, Deep Angelfish, Orinoco Angelfish
Family	Cichlidae
Origin	Upper Orinoco and upper Rio Negro basins, South America
Care Level	Advanced
Temperament	Peaceful
Diet	Omnivore
Tank Level	Middle
Maximum Size	7 inches (18 cm) body length; up to 14 inches (35 cm) total height
Minimum Tank Size	55 gallons (208 liters)
Temperature	78 to 84°F (26 to 29°C)
pH	4.5 to 6.5
Hardness	0 to 5 dGH
Lifespan	10 to 15 years
Breeding	Substrate spawner
Breeding Difficulty	Very Difficult
Compatibility	Peaceful community (soft water species only)
OK for Planted Tanks?	Yes

Classification

Taxonomic Level	Classification
Order	Cichliformes
Family	Cichlidae
Subfamily	Cichlinae
Genus	Pterophyllum
Species	P. altum Pellegrin, 1903

The altum angelfish was described by Jacques Pellegrin in 1903, making it the second species of angelfish to receive a formal scientific description after P. scalare. The species name altum means “tall” or “deep” in Latin, referring to the exaggerated body depth that distinguishes this species from its relatives. There are three recognized species in the genus Pterophyllum: P. scalare (the common angelfish), P. altum, and P. leopoldi (Leopold’s angelfish).

It’s worth noting that many fish sold as “altum angelfish” in pet stores are actually deep-bodied varieties of P. scalare or scalare-altum hybrids. True P. altum have a distinctive notch (saddle) above the nose between the upper lip and the forehead, giving them a steeper, more angular head profile. If the transition from mouth to forehead is smooth and rounded, you’re likely looking at a scalare, not a true altum.

Origin & Natural Habitat

Altum angelfish have a relatively limited natural range compared to the widespread common angelfish. They’re found in the upper Orinoco River basin in Venezuela and Colombia, particularly in tributaries like the Rio Inirida and Rio Atabapo. They also occur in the upper Rio Negro drainage in Brazil and Colombia. These are remote, often difficult-to-access waterways that are far from the typical fish collection routes.

The natural habitat of altums is characterized by extremely soft, acidic water. The pH in their native rivers often drops below 5.0, sometimes reaching as low as 4.0 during certain seasons. The water is typically warm (82-86°F / 28-30°C), heavily stained with tannins from decomposing organic matter, and very low in dissolved minerals. The substrate is usually fine sand or mud covered in leaf litter.

In the wild, altums inhabit areas with dense submerged wood, tangled root structures, and overhanging vegetation. They move slowly through these structures, using their laterally compressed body to navigate between branches and roots. This vertical, narrow body plan allows them to slip through tight spaces that predators cannot follow. They tend to stay in deeper, calmer pools rather than areas with strong current.

Appearance & Identification

The altum angelfish is the tallest of the three Pterophyllum species, with a body depth-to-length ratio that gives it a dramatically more vertical appearance than the common angelfish. A mature altum can stand 14 inches (35 cm) from the tip of the dorsal fin to the tip of the ventral fins, while the body itself reaches about 7 inches (18 cm) in standard length. The overall impression is of a fish that is much taller than it is long.

The most distinctive identification feature is the steep, angular forehead profile with a pronounced notch or saddle above the snout. Common angelfish have a gradual, rounded slope from mouth to dorsal fin, while altums have an abrupt, almost concave indentation. This is the single most reliable way to distinguish a true altum from a deep-bodied scalare.

Coloration consists of a silvery-brown to olive base with three prominent dark vertical bars. The bars are typically bolder and more defined than those on common angelfish. Additional faint barring and reddish-brown streaking may be present between the main bars. The dorsal and anal fins are elongated and may show red or brown spotting. Wild specimens often display subtle reddish or brownish hues that intensify under proper conditions.

Male vs. Female

Sexing altum angelfish is extremely difficult. There are no reliable external differences visible to most keepers. As with common angelfish, the only definitive sexing method is observing the breeding tubes during spawning.

Feature	Male	Female
Body Size	Slightly larger on average	Slightly smaller on average
Nuchal Hump	May develop a small hump with maturity	Smoother forehead profile
Forehead Angle	Steeper in some mature males	Slightly less pronounced
Breeding Tube	Narrow, pointed, angled forward	Wider, blunt, angled backward
Coloration	No reliable difference	No reliable difference

If you’re hoping to breed altums, the standard advice applies: start with a group of 6 or more juveniles and let pairs form naturally over time. Attempting to pair random individuals rarely works with this species.

Average Size & Lifespan

Adult altum angelfish reach a body length of approximately 6-7 inches (15-18 cm), but the total height including the extended dorsal and ventral fins can reach 13-14 inches (33-35 cm). This dramatic vertical span is what makes them so visually striking and why tank height is such an important consideration.

Growth rate is moderate. Altums are slower growing than common angelfish and can take 18-24 months to approach adult size under good conditions. With proper care, they can live 10-15 years in captivity, making them a long-term commitment that rewards patient, dedicated keepers.

Care Guide

Tank Size

A minimum of 55 gallons (208 liters) is needed for a small group of altum angelfish, but 75 gallons or larger is strongly recommended. The critical dimension is tank height. Standard 55 and 75-gallon tanks are typically 20-21 inches tall, which provides adequate room for adult altums. Avoid shallow tanks, as these fish need vertical swimming space to accommodate their tall fin profile.

For a group of 5-6 adults, a 90 to 125-gallon tank with at least 20 inches of water depth provides the best environment. A wider tank also helps by giving each fish enough lateral space to establish personal territory without constant conflict.

Water Parameters

Parameter	Recommended Range
Temperature	78 to 84°F (26 to 29°C)
pH	4.5 to 6.5
General Hardness	0 to 5 dGH
Ammonia	0 ppm
Nitrite	0 ppm
Nitrate	Below 10 ppm

This is where altum angelfish separate themselves from common angelfish. While captive-bred scalare angels do fine in moderately hard, neutral water, altums require genuinely soft, acidic conditions. Most keepers need to use reverse osmosis (RO) water or rainwater to achieve the necessary softness. Tap water with measurable hardness and a neutral-to-alkaline pH is not suitable for altums without modification.

Stability is paramount. Wild-caught altums are sensitive to parameter swings, particularly sudden pH or temperature changes. Get your water chemistry right and keep it consistent. Indian almond leaves, peat filtration, and driftwood all help maintain naturally acidic, tannin-rich water that altums thrive in.

Filtration & Water Flow

Altums come from slow-moving to still water and do not appreciate strong currents. A gentle canister filter or sponge filter works best. If using a canister, diffuse the output with a spray bar or direct it against the glass to minimize water movement. The filtration needs to be effective enough to maintain pristine water quality without creating turbulence.

Regular water changes of 20-30% once or twice weekly are important, but the replacement water must be carefully temperature-matched and have similar chemistry. Adding large volumes of harder, cooler, or more alkaline water during changes is a recipe for stress and disease.

Lighting

Subdued lighting is strongly recommended. Altums come from heavily shaded forest waterways and are visibly stressed under bright illumination. Floating plants are excellent for diffusing overhead light and creating the dappled, shaded environment these fish prefer. A dimmer LED fixture on a gradual timer mimics natural dawn-to-dusk light cycles and reduces stress.

Plants & Decorations

A well-planted tank with tall driftwood pieces is the ideal setup for altum angelfish. Use tall background plants like vallisneria or amazon swords, along with mid-ground plants like java fern and anubias attached to driftwood. Floating plants (amazon frogbit, dwarf water lettuce) are essential for creating shade. The driftwood not only provides visual barriers and hiding spots but also releases tannins that help acidify the water naturally.

Create open swimming areas between planted sections so the altums can glide through the tank without bumping their delicate fins on décor. Avoid sharp-edged rocks or decorations that could tear their elongated dorsal and ventral fins.

Substrate

Fine sand is the ideal substrate for altum angelfish tanks. It mimics their natural habitat, won’t damage delicate fins if they brush against it, and works well with live plants. A layer of dried Indian almond leaves or other botanical leaf litter on top of the sand adds a natural touch, releases beneficial tannins, and provides additional surfaces for biofilm growth that the fish pick at.

Tank Mates

Tank mate selection for altum angelfish is constrained by their need for soft, acidic, warm water and their timid nature. Any companion species must share these water parameter requirements and be peaceful enough not to stress the altums.

Best Tank Mates

• Cardinal tetras – Thrive in the same soft, acidic water altums require. Their small size means very young fish could be eaten, but adults are generally safe
• Rummy-nose tetras – Another soft-water tetra that complements altums well in properly sized tanks
• Sterbai corydoras – Tolerant of the warm temperatures altums prefer and peaceful bottom dwellers
• Pencilfish (Nannostomus spp.) – Gentle, small, and native to similar soft-water habitats
• Hatchetfish – Peaceful surface dwellers that add activity to the upper tank zone
• Apistogramma species – Dwarf cichlids from similar biotopes that occupy the bottom of the tank
• Discus – Can coexist beautifully in large tanks with matching water parameters

Tank Mates to Avoid

• Aggressive cichlids – Any cichlid that will harass or outcompete the altums
• Fin nippers – Tiger barbs, serpae tetras, and other known nippers will destroy the altums’ long fins
• Hard water species – African cichlids, livebearers, and other fish requiring alkaline, hard water are completely incompatible
• Fast, boisterous fish – Active fish that create constant commotion will stress altums into hiding
• Very small fish – Anything that fits in an altum’s mouth is potential prey, including small neon tetras

Food & Diet

Wild-caught altum angelfish can be finicky eaters when first imported, sometimes refusing everything except live foods. This is one of the initial challenges of keeping the species. Newly acquired wild altums may only accept live foods like blackworms, brine shrimp, daphnia, and mosquito larvae for the first few weeks.

With patience, most altums can be weaned onto frozen foods (bloodworms, mysis shrimp, brine shrimp) and eventually high-quality cichlid pellets or flakes. The transition process can take weeks, so don’t get discouraged if your new altums ignore prepared foods initially. Offering a mix of live and frozen foods alongside pellets during the weaning period helps.

Once acclimated, feed altums 2-3 times daily with a varied diet of frozen and prepared foods. A high-quality small to medium cichlid pellet makes a good staple, supplemented with frozen bloodworms, mysis shrimp, and the occasional treat of live food. Avoid overfeeding, as uneaten food degrades water quality quickly in the warm, soft water these fish require.

Breeding & Reproduction

Breeding Difficulty

Very difficult. Captive breeding of true altum angelfish remains one of the greatest challenges in the freshwater hobby. While it has been accomplished, successful breeding events are rare enough to be noteworthy. The difficulty stems from the extreme water parameter requirements, the sensitivity of eggs and fry, and the challenge of obtaining compatible pairs from wild-caught stock.

Spawning Tank Setup

A dedicated breeding tank of 55-75 gallons with tall dimensions is recommended. Provide vertical spawning surfaces such as broad-leafed plants (amazon swords), PVC pipes, or slate pieces. Lighting should be dim, and the tank should be placed in a quiet area with minimal foot traffic. Altums are easily spooked and will eat their eggs if disturbed.

Water Conditions for Breeding

Breeding altums requires extremely soft, acidic water. Target a pH of 4.5-5.5 with hardness as close to 0 dGH as possible. Temperature should be 82-84°F (28-29°C). Pure RO water with minimal remineralization is typically necessary. Some breeders use peat filtration or blackwater extract to achieve the necessary water chemistry.

Conditioning & Spawning

Condition the pair with frequent feedings of high-protein live and frozen foods. Simulating seasonal water level changes through gradually lowering and then raising the water level, combined with slight temperature adjustments, may help trigger spawning behavior. When ready, the pair cleans a vertical surface and deposits eggs in a typical angelfish fashion. Clutch sizes are generally smaller than common angelfish, often 100-200 eggs.

Egg & Fry Care

Eggs are highly susceptible to fungus in anything other than extremely soft, acidic water. Many breeders add methylene blue to protect the eggs. Hatching occurs in approximately 48-72 hours at 82°F (28°C). The fry are tiny and delicate, requiring infusoria or commercially prepared liquid fry food initially, followed by freshly hatched baby brine shrimp once large enough.

Fry mortality is typically high, especially during the first week. Maintaining pristine water quality with very gentle filtration (a mature sponge filter is ideal) and performing careful, small water changes are critical. The parents may or may not care for the fry successfully. Many first-time altum parents eat their eggs or fry, and even experienced pairs may fail if disturbed.

Common Health Issues

Ich (White Spot Disease)

Altums are particularly susceptible to ich during the acclimation period after import. Stress from shipping, combined with exposure to new water conditions, can trigger outbreaks. Treatment should be approached carefully, as altums can be sensitive to medications. Raising temperature to 86°F (30°C) is often the safest first approach, sometimes combined with low-dose salt treatment (though be cautious with salt in very soft water). Commercial ich medications should be used at half-dose initially to gauge the fish’s tolerance.

Internal Parasites

Wild-caught altums frequently carry internal parasites including Hexamita, intestinal worms, and flagellates. Symptoms include white stringy feces, weight loss, loss of appetite, and lethargy. Prophylactic treatment of newly imported fish with metronidazole and praziquantel is common practice among experienced altum keepers. A thorough quarantine period of 4-6 weeks is strongly recommended.

Bacterial Infections

Stress-related bacterial infections can manifest as fin rot, body sores, or cloudy eyes. These are almost always secondary to poor water quality or the stress of importation. Maintaining pristine water conditions is the best prevention. Treatment with broad-spectrum antibiotics like kanamycin may be necessary for active infections.

pH Shock

Because altums require such acidic water, they are vulnerable to pH shock when exposed to neutral or alkaline conditions. Symptoms include erratic swimming, rapid breathing, and loss of balance. This is most common during water changes with improperly prepared replacement water or when fish are transferred between tanks with different chemistry. Always match replacement water to current tank parameters as closely as possible.

Common Mistakes to Avoid

• Treating altums like common angelfish. They are a completely different animal in terms of water requirements and sensitivity. Care guides for P. scalare do not apply
• Using untreated tap water. Most tap water is too hard and alkaline for altums. RO water or very soft water is typically necessary
• Buying mislabeled fish. Many fish sold as “altum angelfish” are deep-bodied scalare or hybrids. Learn to identify the distinctive forehead notch of true P. altum
• Skipping quarantine. Wild-caught altums almost always carry parasites. Quarantine for at least 4-6 weeks and consider prophylactic deworming
• Using tanks that are too short. Altums need vertical space. A long, shallow tank constrains their natural posture and fin extension
• Rushing acclimation. Take your time introducing altums to new water. Drip acclimation over 2-3 hours is the minimum. These fish do not handle rapid parameter changes well

Where to Buy

True altum angelfish are not as widely available as common angelfish. They are a specialty fish that typically needs to be sourced from importers, specialty online retailers, or occasionally from local hobbyists who have established groups. Because most altums are wild-caught, availability is often seasonal, coinciding with collection periods in their native range.

Check with Flip Aquatics and Dan’s Fish for availability, as both carry specialty South American species and ship with live arrival guarantees. When buying altums, ask the seller how long the fish have been in their facility and whether they’ve been eating prepared foods. An altum that has been in a retailer’s tanks for several weeks and is eating well is a much safer purchase than a freshly imported specimen.

When selecting altum angelfish, look for the distinctive forehead notch that confirms true P. altum identification. Choose fish with clear eyes, intact fins, and good body condition. Avoid any fish with pinched bellies, clamped fins, or visible lesions. If possible, watch them eat before buying.

Frequently Asked Questions

What’s the difference between altum and common angelfish?

The altum angelfish (P. altum) is a distinct species from the common angelfish (P. scalare). Altums are taller, have a characteristic notch above the nose, require soft acidic water (pH 4.5-6.5), and are almost exclusively wild-caught. Common angelfish are widely captive-bred, available in many color varieties, and tolerate a much broader range of water conditions.

Are captive-bred altum angelfish available?

Captive-bred altums do exist, but they are rare and command premium prices. The vast majority of altum angelfish in the hobby are wild-caught imports from Colombia and Venezuela. If you find captive-bred altums, they are generally hardier and easier to acclimate than wild-caught specimens, making them worth the extra cost.

Can I keep altums with common angelfish?

This is generally not recommended. The water parameter requirements are significantly different. Altums need very soft, acidic water (pH 4.5-6.5, 0-5 dGH), while most captive-bred scalare do best in neutral to slightly acidic, moderately soft water. There is also a risk of hybridization, and the more assertive scalare may outcompete the more timid altums for food.

Do I need an RO system for altum angelfish?

In most cases, yes. Unless your tap water is naturally very soft and acidic (unlikely for most hobbyists), you will need an RO unit to produce water soft enough for altums. An RO system is one of the most important investments for keeping this species successfully. You can remineralize the RO water slightly with a product designed for soft-water fish to ensure essential minerals are present.

How tall should an altum angelfish tank be?

At least 20 inches of water depth, with 24 inches being ideal. Adult altums can reach 14 inches from fin tip to fin tip, so they need significant vertical space. Standard 55 and 75-gallon tanks (typically 20-21 inches tall) work, but taller custom tanks or standard 90-gallon tanks (24 inches tall) are even better.

Closing Thoughts

The altum angelfish is not a beginner fish, and it’s not even an intermediate fish. It’s a species for experienced keepers who have the equipment, knowledge, and patience to provide the specific conditions these wild angels require. Soft water, stable chemistry, warm temperatures, a calm environment, and a willingness to invest in proper equipment (including an RO system) are the baseline requirements.

But for those who can meet the challenge, altum angelfish are among the most rewarding species in the freshwater hobby. Watching a group of adult altums drift through a planted, blackwater-style aquarium is an experience that simply doesn’t compare to anything else. If you’ve mastered common angelfish and discus and you’re looking for the next level, the altum is waiting for you. Just make sure you’re ready for it.

References

• Seriously Fish – Pterophyllum altum species profile. seriouslyfish.com
• FishBase – Pterophyllum altum Pellegrin, 1903. fishbase.se
• Kullander, S.O. (2003). Family Cichlidae. In: Reis, R.E., Kullander, S.O. & Ferraris, C.J. (eds.) Check List of the Freshwater Fishes of South and Central America. Porto Alegre: EDIPUCRS.
• Practical Fishkeeping – Altum angelfish profile. practicalfishkeeping.co.uk