Pasca
Paragoniates alburnus
The Pasca features a slender body with a silver hue, a pointed snout, and a pronounced dorsal fin, displaying iridescent blue reflections.
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About the Pasca
A silvery midwater characin and the only member of its genus, P. alburnus ranges across the Amazon and Orinoco drainages. It is a fairly chunky tetra for its length and does best in groups; it can be a bit pushy, so give it space and tankmates of similar size.
Also known as
Quick Facts
Size
6.7 cm SL
Temperament
Semi-aggressive
Difficulty
Intermediate
Min Tank Size
55 gallons
Lifespan
5 years
Origin
South America - Amazon and Orinoco basins
Diet
Omnivore - small live and frozen foods plus quality flakes/pellets
Water Parameters
23-27°C
5.6-7.8
3-10 dGH
Need a heater for this species?
This species needs 23-27°C in a 55 gallon tank. Use our heater calculator to find the right wattage.
Calculate heater sizeCare Notes
- Start with a 55-gallon or larger tank and leave open midwater swimming space; this chunky tetra does best kept in a group rather than alone.
- Hold water at 23-27 C, pH 5.6-7.8, and 3-10 dGH; keep conditions steady within that range.
- Feed a varied omnivore diet of small live and frozen foods alongside quality flakes or pellets.
- Choose tankmates of similar size and temperament; they can be pushy and may hassle tiny or slow fish.
- Provide open lanes for swimming with some cover to break sightlines so any chasing has places to dissipate.
- With good care, expect a lifespan of about 5 years.
Compatibility
Good Tankmates
- Their own species in a group of 6+ to spread any pushiness; roomy 55 gal+ with open midwater works best
- Robust, similarly sized schooling characins (e.g., red-eye or bleeding heart tetras) that match their pace and are not easily bullied
- Corydoras catfish and other peaceful bottom foragers that stay out of midwater
- Small to medium Loricariids (bristlenose pleco, Rineloricaria) that are armored and ignore midwater scuffles
- Peaceful, non-predatory dwarf cichlids that hold bottom territory (Laetacara, keyhole, larger Apistogramma) with cover and sightlines
Avoid
- Very small community fish and dwarf shrimp (neons, embers, cherry shrimp) that can be harassed or taken as prey
- Delicate top dwellers like hatchetfish and pencilfish that stress under active, pushy midwater fish
- Slow or long-finned species (angelfish, fancy bettas, gouramis) that invite fin-nipping
- Large aggressive or predatory fish (big cichlids, pike cichlids, bichirs) that may harass or eat them
Pasca (Paragoniates alburnus) is a silvery, midwater characin and the only member of its genus. Native to the Amazon and Orinoco drainages, it is a fairly chunky tetra for its length, topping out around 6.7 cm SL. It is semi-aggressive, does best in groups, and benefits from ample swimming space. Expect around 5 years of lifespan with steady care.
Origin and range
Freshwater South America: widespread across the Amazon and Orinoco basins. In aquaria it behaves as a midwater fish, reflecting its open-water habits in nature.
Aquarium setup and water conditions
Give Pasca room. A minimum of 55 US gallons is recommended, with open swimming space for a group. Keep the water clean and well filtered, and avoid crowding to limit pushy behavior within the group.
- Temperature: 23-27 C
- pH: 5.6-7.8
- Hardness: 3-10 dGH
- Water type: freshwater
Keep Pasca in a group. More space and more conspecifics spread out the inevitable jostling and make day-to-day behavior more manageable.
Behaviour and tankmates
Pasca is semi-aggressive and can be a bit pushy, especially in tight quarters. It is a midwater fish that does best in groups; solitary individuals tend to be more nippy or restless.
- Choose tankmates of similar size and activity level.
- Avoid very small or very slow fish that could be harassed.
- Provide enough space so groups can establish a pecking order without constant chasing.
Diet and feeding
An omnivore that appreciates variety. Offer small live and frozen foods alongside quality flakes or micro-pellets. Several modest feedings across the week are better than large, infrequent meals.
- Small live/frozen items: daphnia, brine shrimp, bloodworms
- Quality flakes and small pellets as staples
- Rotate foods to maintain condition and color
Common problems and how to avoid them
- Crowding: increases chasing and nipping. Use a 55+ gallon tank and keep a proper group.
- Mismatch with tiny or delicate tankmates: choose similarly sized, robust companions.
- Unstable water: stick to the listed ranges and keep water clean with regular maintenance.
- Monotonous diet: mix live/frozen with quality dry foods to keep them in good condition.
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