Blue Pincher Macro

Macrobrachium vollenhovenii

📍 West Africa (primarily Ghana and Cameroon)

Macrobrachium vollenhovenii, commonly called the Blue Pincher Macro, is a large freshwater shrimp prized for its striking blue coloration and impressive size. These aggressive omnivores require spacious tanks and are best kept singly or in small groups with careful monitoring. They are fascinating but demanding inhabitants suited to experienced aquarists.

Size5.9"

Min Tank40g

aggressive

Zonebottom

Care Guide

Diet

Blue Pincher Macros are opportunistic omnivores that consume biofilm, algae, detritus, and small invertebrates. Offer sinking pellets, blanched vegetables (zucchini, spinach), and occasional protein sources like bloodworms or small crustaceans. Feed 2-3 times weekly, removing uneaten food within 24 hours.

Behavior

These large, territorial shrimp are highly aggressive and will attack or consume smaller tank mates and even conspecifics. They are primarily nocturnal and spend much of their time foraging along the substrate and in crevices. Males are particularly combative and should be housed individually or with extreme caution.

Breeding

Breeding in freshwater is extremely difficult and rarely achieved in home aquaria. Females produce eggs that typically require brackish water conditions for larvae to develop successfully. Most wild-caught specimens are imported as adults, making captive breeding impractical for most hobbyists.

Tank Mates

Bristlenose Pleco

May be attacked or consumed; only suitable in very large tanks with ample hiding

caution

Otocinclus

Too small; will be predated upon by aggressive macros

caution

Anubias Nana

Hardy plant for decoration and biofilm growth; shrimp will not destroy it

good

Java Moss

Provides biofilm, cover, and foraging substrate without being harmed

good

Marimo Moss Ball

Inert decoration that provides biofilm and does not interact with shrimp

good

Common Diseases

Copper Toxicity

Symptoms

Lethargy, loss of appetite, discoloration, molting difficulties, death

Treatment

Use only copper-free medications and fertilizers; perform large water changes; avoid tap water with high copper content; use RO water if necessary

Molting Problems

Symptoms

Inability to shed exoskeleton, stuck molt, death shortly after molting

Treatment

Ensure adequate calcium and minerals in water; maintain stable pH and temperature; provide plenty of hiding spots; avoid handling during molt

Parasitic Infections (Flukes, Copepods)

Symptoms

Excessive grooming, visible parasites on body, lethargy, loss of appetite

Treatment

Quarantine affected shrimp; perform salt baths (1-2 teaspoons per gallon for 10-15 minutes); use copper-free parasite treatments; improve water quality

Bacterial Shell Infection

Symptoms

Discoloration, soft spots on exoskeleton, cloudy appearance, lethargy

Treatment

Improve water quality with frequent partial water changes; maintain optimal temperature and pH; remove affected shrimp to quarantine; use antibacterial treatments if severe