Giant Freshwater Prawn
Macrobrachium rosenbergii
The Giant Freshwater Prawn (Macrobrachium rosenbergii) is a semi-aggressive fish that's easy to keep. Give it a tank of at least 75 litres (20 US gallons), water held at 75-86°F, and a pH of 6.5-8.
Captive lifespan reflects typical experience in a home aquarium, not maximum recorded age; genetics, sourcing, and care vary.
Natural distribution
Various
We don't shade a region on this simplified map - your text may be Europe-only, worldwide, listed as "Various," captive-only, or outside the five areas used in the stocking calculator. That tool still scores whether your fish come from similar parts of the world.
Regional colours match the stocking calculator's origin map.
Giant Freshwater Prawn Tank Setup
A tank of 75 litres (20 US gallons) or more with rock-steady water suits them best - keep it at 75-86°F with a pH around 6.5-8. Stable conditions matter most, as shrimp struggle to moult and breed when parameters bounce around. They grow to around 32 cm, so plan the tank size and filtration for a full-grown adult rather than the small juvenile you see in the shop.
What Do Giant Freshwater Prawns Eat?
They're bottom feeders, so give them sinking wafers, tablets, or frozen treats like bloodworm once the lights go down. Flakes that never reach the bottom leave them hungry even when the tank looks well-fed.
Giant Freshwater Prawn Tank Mates
Predatory; may eat small fish or inverts. The Giant Freshwater Prawn is semi-aggressive, which is the first thing to weigh up when you choose tank mates. It's predatory, so anything small enough to fit in its mouth will be treated as food rather than a companion. Before you buy, run your full stocking list through our stocking calculator. It weighs temperament, adult size, and water needs together, which a single species page can't do on its own.
Are Giant Freshwater Prawns Good for Beginners?
Not a sensible first purchase. Get the tank cycled, keep easier fish stable for a year, then revisit if you still want the extra work this species demands.
Giant Freshwater Prawn - frequently asked questions
What size tank do Giant Freshwater Prawns need?
Giant Freshwater Prawns need a tank of at least 75 litres (20 US gallons). A bigger tank is always easier to keep stable, and gives them more room to settle in and behave naturally.
What water parameters do Giant Freshwater Prawns need?
Keep them at 75-86°F with a pH of 6.5-8, steady rather than chased to an exact figure. In a cycled tank, ammonia and nitrite should both read 0 ppm, with nitrate kept low through regular water changes.
What do Giant Freshwater Prawns eat?
Giant Freshwater Prawns are bottom feeders. Give them sinking wafers, tablets, and frozen foods that settle on the substrate, ideally after the lights go off. Feed small amounts once or twice a day, and remove anything they don't eat.
Are Giant Freshwater Prawns good for beginners?
Yes - Giant Freshwater Prawns are a reasonable beginner fish once the tank is cycled and parameters are stable. Add them after ammonia and nitrite read 0 ppm, not the same day you fill the tank.
Building a community? Run the full list through the stocking calculator before you add anything else.
Great tank mates
Chosen from temperament, overlapping temperature/pH bands, plausible minimum tank footprints, and size versus yours in App-aquatic data. Hobby nuance always wins - verify stocking and temperament before purchasing.
Check Giant Freshwater Prawn against any other fish → Compares water parameters, predation risk, fin nipping and tank size, and draws both at life size.
Fish to avoid mixing with Giant Freshwater Prawns
These well-known species are commonly sold alongside this fish but are not recommended tank mates - verify before purchasing.
- OscarPredator - Oscar will eat or injure smaller tank mates
- Pea PufferPredator - Pea Puffer will eat or injure smaller tank mates
- Clown LoachFin nipper - will shred the fins of peaceful fish
