Giant freshwater prawn

Care at a glance

Overview

This is a huge, predatory prawn that treats most tankmates as food, so keep it on its own or at most as a single pair in a large tank of around 200 liters or more with a tight lid. It spends its time on the bottom, walking the substrate and scavenging, and mature males carry enormous claws that can approach twice their body length. Give it open floor space, sturdy hiding spots for molting, and hard, warm water. Feed it well on sinking pellets, mussel, prawn, earthworms, and the occasional vegetable, since a hungry one is even more likely to grab a fish. Do not trust it with anything small enough to catch.

In the wild

In the wild this prawn ranges through warm lowland rivers and estuaries from India east to New Guinea, moving between fresh and brackish water over its life. Females release their larvae into salty estuary water, which is why it breeds so rarely in tanks. Recreate the adult habitat with warm water from 24 to 30 C, a neutral to hard, alkaline chemistry around pH 7.0 to 8.5, a soft sand or fine gravel floor, and plenty of wood and rock to break up sight lines. Good filtration and steady oxygen matter, since it is a large, messy feeder.

Good to know

Macrobrachium spinipes belongs to the palaemonid prawns and is one of the giants of the group, with males reaching about 32 centimeters in body length and weights over half a kilogram. For years it was farmed around the world as Macrobrachium rosenbergii, until the eastern populations were recognized as a separate species. Breeding is hard in captivity because the tiny larvae cannot develop in pure freshwater and need brackish conditions to survive, so almost all tank specimens are farm raised or wild caught.

Did you know

The giant freshwater prawn is farmed by the million for food, and it was only after decades of aquaculture that scientists split the eastern stock off from the western one as its own species.

Common questions

Related species

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• Lollipop prawn

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• Taiwanese long claw prawn

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• 

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