Ninja shrimp

Caridina serratirostris

Also known as Batik ninja shrimp, Christmas shrimp

FreshwaterShrimp

Care at a glance

Temperature: 73–82°F (23–28°C)
pH: 6.5–7.8
Adult size: 1.2 in (3 cm)
Minimum tank: 5 gal (20 L)
Temperament: Peaceful
Social behavior: Social
Swim level: Bottom
Difficulty: Medium
Breeding: Hard
Rarity: Rare
Origin: Coastal streams from East Africa across the Indo-Pacific
Family: Atyidae

Overview

The ninja shrimp is a small, peaceful grazing shrimp best kept as a group in a planted or hardscaped nano tank. Buy a handful so they feel secure, since they are sociable and settle better in numbers. They spend the day working over rock, wood, and leaf litter for algae and biofilm, and they pose no threat to plants or calm tankmates. Keep them only with small, gentle fish or other shrimp, nothing large enough to hunt them. Feed a staple shrimp food plus the odd blanched vegetable and a little frozen food. A stable, mature tank of around 20 liters or more is plenty.

In the wild

Ninja shrimp live in lowland coastal streams from East Africa across the Indo-Pacific, in soft cover of leaf litter, roots, and stones close to where fresh water meets the tide. A tank with plenty of hiding places, some botanicals, and gentle to moderate flow suits them. Hold the water warm at 23–28 C and from slightly acidic to slightly alkaline, roughly pH 6.5–7.8, and keep it clean and stable.

Good to know

Caridina serratirostris is a member of Atyidae, the dwarf shrimp family, and grows to only about 3 centimeters. It is amphidromous, which makes breeding hard in captivity: the larvae hatch in fresh water but need brackish conditions to develop, so ordinary freshwater tanks do not produce a self-sustaining colony. Nearly all of the shrimp in the trade are still wild caught.

Did you know

The name fits its trick. Startled, a ninja shrimp darts off and can change color in seconds, cycling through reds, browns, and near-black to blend into the streambed and slip a predator's eye.