TankBud

Krieg's tetra

Serrapinnus kriegi

Also known as Kriegi tetra

FreshwaterFish

Krieg's tetra (Serrapinnus kriegi)
The Wet Spot Tropical Fish · Used with permission

Care at a glance

Temperature
68–79°F
20–26°C
pH
5.5–7.2
Adult size
0.9 in
2.4 cm
Minimum tank
11 gal
40 L
Temperament
Peaceful
Social behavior
Schooling
Swim level
Middle
Difficulty
Medium
Breeding
Egg layer
Rarity
Rare
Family
Characidae
Origin
Paraguay basin, Paraguay and Brazil

Overview

Krieg's tetra is a tiny subtropical schooling fish for a calm nano or planted community. Keeping it well calls for some experience.

Did you know

A single Krieg's tetra looks modest, but a group of twenty or more becomes a moving display.

Caring for the Krieg's tetra

Keep a group of Krieg's tetras in 11 gal (40 L) or more, with dense planting. Fine-leaved plants, gentle flow and clean, stable water suit them.

They come from cooler subtropical water, so in many climates they can be kept in an unheated room with no heater at all. That makes them one of the cheapest ways into keeping South American micro fish. Keep the water at 68 to 79°F (20 to 26°C), with a pH of 5.5 to 7.2 and soft to moderate hardness.

Feed very small foods, such as fine flake, crushed micro pellets, cyclops, microworm and baby brine shrimp. Krieg's tetras are completely peaceful. Good tank mates are other small, gentle fish such as micro rasboras, small tetras and pygmy corydoras.

As in the rest of the Cheirodontinae, male Krieg's tetras carry small hooks on the anal fin. These serve as contact organs when pairing. Krieg's tetras lay eggs, but home breeding is not formally recorded.

Good to know

Serrapinnus kriegi is a miniature member of the Cheirodontinae, within the characin family Characidae. Schindler described it in 1937, and it shows a wedge of gold at the base of the tail.

In the wild

Krieg's tetra lives in the Paraguay River basin, in Paraguay and Brazil. Its home is weedy, slow-moving or still water, among dense vegetation, leaf litter and submerged wood. These subtropical waters cool in winter.

Weekly picks

Tank mates

The Krieg's tetra 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.

Check the full mix in the stocking calculator

Common questions

What size tank does a Krieg's tetra need?

A Krieg's tetra needs at least 11 gal (40 L). It spends most of its time in the middle.

What temperature and pH does a Krieg's tetra need?

A Krieg's tetra is comfortable at 68–79°F (20–26°C) with a pH of 5.5–7.2.

What does a Krieg's tetra eat?

A Krieg's tetra needs very small foods. Offer fine flake, crushed micro pellets, cyclops, microworm and baby brine shrimp.

How big does a Krieg's tetra get?

An adult Krieg's tetra reaches about 0.9 in (2.4 cm).

Does a Krieg's tetra need a group?

Yes. A Krieg's tetra is a schooling species and should be kept in a group, not singly.

How can you tell a male Krieg's tetra from a female?

Males carry small hooks on the anal fin, as in the rest of their group. They use them as contact organs when pairing.

How does a Krieg's tetra breed?

Krieg's tetras lay eggs, but breeding them at home is not formally recorded.

Related species