The Amano shrimp (Caridina multidentata, formerly Caridina japonica) is one of the most popular and hardworking freshwater aquarium inhabitants in the world. It was popularised by legendary aquascapist Takashi Amano in the 1980s. These translucent scavengers are celebrated as the ultimate clean-up crew. This is due to their relentless appetite for nuisance algae.

Key Characteristics

• Appearance: They have a semi-transparent, translucent body with a distinct light stripe running down the spine. Their flanks feature rows of reddish-brown spots (which look like round dots on males and longer dashes on females).
• Size: They are notably larger than cherry shrimp, with males reaching 1.5 to 2 inches (3.8–5 cm) and females growing larger at 2 to 3 inches (5–7.6 cm).
• Lifespan: They typically live 2 to 3 years, though they can reach up to 5 years under optimal care.

Diet & Aquarium Utility

Amano shrimp are legendary algae eaters. While many dwarf shrimp only eat soft film, Amanos will vigorously consume tougher varieties like hair algae, string algae, and diatoms. They will even pick at stubborn black beard algae. However, this only happens if they are hungry enough.

In addition to algae, they act as general scavengers that consume leftover fish food, decaying plant matter, and detritus. Because they lack cutting or tearing mouthparts, they are entirely safe around small fish and delicate live plants.

Ideal Tank Conditions

Amano shrimp are exceptionally hardy and adaptable, making them excellent choices for both beginners and experienced aquarists.

• Tank Size: Minimum of 20 to 35 litres (around 5 to 10 gallons), ideally kept in groups of 5 or more.
• Temperature: 18°C to 28°C (64°F to 82°F).
• Water Chemistry: pH of 6.5 to 7.5, preferring slightly harder water to facilitate healthy shell molting.
• Decor: They thrive in densely planted tanks featuring plenty of driftwood, rocks, and hiding spaces.
• Warning: They are highly sensitive to copper, so ensure any aquarium medications or plant fertilizers used are completely copper-free.

Note: Always keep a secure lid on your aquarium. Amano shrimp are notorious climbers and will occasionally escape the tank if given the opportunity.

The Breeding Challenge

While adult Amano shrimp live entirely in freshwater, breeding them in captivity is incredibly difficult. In nature, they are amphidromous. The adult shrimp spawn in freshwater rivers, but the microscopic larvae hatch and wash downstream into brackish/saltwater estuaries to develop. Once they transform into juvenile shrimp, they migrate back up into freshwater streams. Because of this complex life cycle, almost all Amano shrimp in the hobby are wild-caught. Alternatively, they are raised by highly specialized breeders.