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Species profile

Threespot Headstander

Pseudanos trimaculatus

Common names: Threespot Headstander

Recognized speciesHeadstanders and Leporinus

Adult size

Up to 12.5 cm

Up to 12.5 cm

Countries of origin

  • See all stock from Argentina
  • See all stock from Brazil
  • See all stock from Ecuador
  • See all stock from Guyana
  • See all stock from Peru

Good fit for your tank?

Good fit for

  • A keeper who has researched this fish and can match its needs

Think carefully if

  • You only want to keep one or two, because this fish needs a group of 5 or more
  • You keep slow fish with long fins, which it may nip
  • You keep shrimp you want to protect

A slim headstander with three dark spots along its side, formerly known as Anostomus trimaculatus. Keep a group of at least 5 in 85 litres or more.

Appearance and Identification

A slim headstander with three dark spots along its side, formerly known as Anostomus trimaculatus. It does best in a group, and it can be territorial.

Check the scientific name when buying, as common names vary between sellers and countries.

Usually hard to sex, although females are often rounder.

Tank Requirements

Suggested filter
About 170–260 litres an hour
Suggested heater
About 75–125 W for this tank
Minimum tank volume
85 litres
Minimum tank length
63 cm
Minimum group size
5
Recommended group size
8
Activity level
Active
Flow preference
Low
Planting preference
Lightly planted
Hiding places
Yes
Lid recommended
Yes
Jumping risk
High

A long tank with a tight lid is best, because these fish jump. Use tough plants or wood, as soft plants are often eaten.

Behaviour and Tankmates

An active fish that often swims nose-down as it picks at surfaces for food.

Often does best in a group, which spreads out aggression between individuals.

Can be quarrelsome with its own kind and similar-looking fish.

Keep with robust fish of a similar size. It may nip long fins. It may nip the fins of slow or long-finned fish, and a larger group usually reduces this. It is likely to eat shrimp.

Check tankmates for this species

Water Parameters

Temperature
23–27 °C
pH
6–7.5
GH
1–18
Stability importance
Important

Fairly tolerant of different water, if it is clean and stable. Keep the temperature steady.

Parameter caveat
Keep up regular water changes, and acclimatise new fish slowly.

Feeding

Diet types
Herbivore, Omnivore
Feeding frequency
Daily
Preferred foods
  • Spirulina or algae wafersShould make up much of the diet.
  • Blanched vegetablesCourgette, cucumber and peas work well. Remove leftovers within a day.
  • Small frozen foodsAn occasional addition for protein.

Takes plant matter as well as small foods. Include plenty of vegetable food.

Feed small amounts, and remove anything left after a few minutes.

Breeding

Breeding type
Egg Scatterer
Breeding difficulty
Moderate
Parental care
None
Baby foods
  • InfusoriaNeeded for the first days, because most fry are very small.
  • Newly hatched brine shrimpIntroduce as soon as the fry can take it.

An egg scatterer with no parental care. Adults eat eggs and fry, so use a separate tank with fine plants, moss or mesh on the bottom, and remove the adults after spawning. The fry need very small foods at first.

Habitat and Origin

Geographic origin
Argentina, Brazil, Ecuador, Guyana, Peru, South America
Natural habitat
River
Audience level
Intermediate

Classification

Profile type
Recognized species
Genus
Pseudanos
Family
Anostomidae
Species group
Fish, Headstanders and Leporinus

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