False hemiodus
Argonectes longiceps
FreshwaterFish
Care at a glance
- Temperature
- 75–84°F
- 24–29°C
- pH
- 5.5–7.0
- Adult size
- 11.8 in
- 30 cm
- Minimum tank
- 159 gal
- 600 L
- Temperament
- Peaceful
- Social behavior
- Schooling
- Swim level
- Middle
- Difficulty
- Difficult
- Breeding
- No record
- Rarity
- Rare
- Family
- Hemiodontidae
- Origin
- Orinoco and Amazon basins
Overview
The false hemiodus is a large, nervous, fast-swimming schooler that cruises the open middle water. Keeping a group well takes experience and a very big tank.
Did you know
The false hemiodus swims dead level, breaking a family habit. Its close relatives in the genus Hemiodus rest and swim at a distinct head-up, oblique tilt. That is one of the quickest ways to tell it apart from its cousins.
Caring for the false hemiodus
A settled group of false hemiodus wants a long tank of around 159 gal (600 L) or more. Give the group clear swimming lanes and a sandy floor, with strong, steady water movement and high oxygen. Bright open water and current matter far more than decor.
Keep the water soft and warm, at 75 to 84°F (24 to 29°C), with a pH of 5.5 to 7.0. Feed sinking and frozen foods with some vegetable matter.
Keep it in a group of six or more, because lone fish and small groups panic and crash into the glass. Its tank mates should be other large but peaceful fish, such as silver dollars or big characins. Leave out anything small enough to be treated as food. Aquarium breeding is unrecorded.
Good to know
Argonectes longiceps is a hemiodontid, a slender silver fish built for open-river cruising. Its name means long head, describing the drawn-out snout.
In the wild
The false hemiodus swims in large, often blackwater channels of the Orinoco and Amazon basins, the Negro among them. It favors swift, open, sandy stretches.
Weekly picks
Tank mates
The false hemiodus is a peaceful, schooling species that keeps to the middle. These picks share a community profile with it, are safe together in both directions, and overlap on water type, temperature and pH.
Blue acara
Andinoacara pulcher
Freshwater5.9 in (15 cm) · 42 gal (160 L)72–82°F (22–28°C)
Yoyo loach
Botia almorhae
Freshwater6.3 in (16 cm) · 42 gal (160 L)66–81°F (19–27°C)
Boeseman's rainbowfish
Melanotaenia boesemani
Freshwater4.3 in (11 cm) · 29 gal (108 L)81–86°F (27–30°C)
Lilith demonfish
Satanoperca lilith
Freshwater11.8 in (30 cm) · 159 gal (600 L)77–84°F (25–29°C)
Apollo shark minnow
Luciosoma setigerum
Freshwater11.8 in (30 cm) · 106 gal (400 L)72–81°F (22–27°C)
Giant upside-down catfish
Synodontis batensoda
Freshwater11.8 in (30 cm) · 79 gal (300 L)72–81°F (22–27°C)
Common questions
What size tank does a false hemiodus need?
A false hemiodus needs at least 159 gal (600 L). It spends most of its time in the middle.
What temperature and pH does a false hemiodus need?
A false hemiodus is comfortable at 75–84°F (24–29°C) with a pH of 5.5–7.0.
What does a false hemiodus eat?
A false hemiodus eats sinking and frozen foods with some vegetable matter.
How big does a false hemiodus get?
An adult false hemiodus reaches about 11.8 in (30 cm).
Does a false hemiodus need a group?
Yes. A false hemiodus is a schooling species and should be kept in a group, not singly.
How does a false hemiodus breed?
The false hemiodus has no recorded aquarium breeding.
Related species
11 in (28 cm)159 gal (600 L)75–84°F (24–29°C)Smallscale hemiodus
Hemiodus microlepis
11 in (28 cm) · 159 gal (600 L)
7.1 in (18 cm)66 gal (250 L)73–82°F (23–28°C)Slender hemiodus
Hemiodus gracilis
7.1 in (18 cm) · 66 gal (250 L)
6.3 in (16 cm)106 gal (400 L)75–82°F (24–28°C)Fourspot hemiodus
Hemiodus quadrimaculatus
6.3 in (16 cm) · 106 gal (400 L)
7.5 in (19 cm)106 gal (400 L)75–84°F (24–29°C)Fowler's hemiodus
Bivibranchia fowleri
7.5 in (19 cm) · 106 gal (400 L)
11.8 in (30 cm)65 gal (245 L)77–86°F (25–30°C)Chocolate cichlid
Hypselecara temporalis
11.8 in (30 cm) · 65 gal (245 L)
11.8 in (30 cm)50 gal (190 L)39–75°F (4–24°C)Comet
Carassius auratus
11.8 in (30 cm) · 50 gal (190 L)