Chocolate shrimp, Macrobrachium dayanum

The chocolate shrimp belongs to the large arm shrimp. It is also traded as Red Rusty shr imp. Its scientific name is Macrobrachicum dayanum. Macrobrachium assamense is also traded under the name Red Rusty shrimp. The species look extremely similar, especially in the juvenile stage. In the wild, the animals live in freshwater rivers in southern India. The chocolate shrimp has a maximum life expectancy of about 3 years. The females reach a size of about 7 cm, the males about 9 cm. However, the two sexes can be distinguished not only by the final size. The males have clearly larger claw arms. As with all large-armed shrimp, the second pair of claws is the largest, not the first as in crayfish. Females, like most large-armed shrimp, are more bulky in build and have a downward extended pleon, males are more slender. Recommended Macrofeed. 

Overall, Macrobrachicum dayanum is uncomplicated to keep. The tank should hold at least 60 liters for this quite large territorial shrimp and should not be very densely planted, so that the animals feel comfortable. Furthermore sufficient hiding places and a good structure by roots and stones must be created. Especially during and after molting the animals need hiding places.

The chocolate shrimp are very adaptable and feel very comfortable at temperatures of 20-30°C, a total hardness of 6-18 dGH and a carbon hardness of 3-15. The pH value should be between 7 and 8. The chocolate shrimp are rather crepuscular and nocturnal and show themselves less often during the day, but also come out of their hiding places during the day to feed.

Among themselves it comes with the territorial animals more often to quarrels and fights, which can have the consequence that a group then consists only of a male and a few females. If too many animals are kept together in too small a space, atypical behavior and dwarfism may occur. Per animal we recommend 20 l, and at least 60 l for keeping (60-70 l aquarium for 1 male and 2 females).

When it comes to food, the large-armed shrimp are not very demanding. Their diet ranges from fish food, small snails and catfish ro ds to mosquito larvae and small artemia crabs/stream shrimp. Catfish rods are especially highly recommended, as they contain cellulose, which aids in digestion. Some chocolate large arm shrimp will occasionally attack the planting of the tank, but this is not a cause for concern, the plant population is usually not endangered by this.

After successful mating the female carries up to 60 eggs under the pleon for about 4-6 weeks and releases fully developed young after this gestation period.

Basically the chocolate shrimp can be socialized. However, care should be taken, because the shrimp may eat smaller fish or even sleeping fish. Also snails and dwarf or also fan shrimps are eaten. The juveniles are almost never chased, which makes breeding possible even in the parent tank. Nevertheless it is easier and safer to raise the young in the breeding tank.

Our food recommendation: The soft granulate of the Natureholic MacroFeed consists of biologically balanced animal components that large-armed shrimps would find in nature in this or a similar way. This supports  in a completely natural way the moulting, the development and a healthy growth of your fascinating large arm shrimps in the aquarium.

Our plant recommendation: For planting, use NatureHolic InVitros. These are free of snails, planarians and other unwanted co-inhabitants. Also free of algae spores, bacteria and fungi.

Expert Tip: We recommend for fish keeping the NatureHolic 3 Phase Liquid. The care set offers the best all-round protection for your animals. It ensures optimal conditions for successful breeding and keeping.