The most striking feature of the red rhinoceros shrimp (lat. Caridina gracilirostris) is its extremely long, reddish “nose” (Rostrum), which led to the unmistakable species name. This can break off during rivalry fights or during transport, for example, but it grows back completely during the next moult, which means that the animals retain their characteristic appearance for a long time. Red rhinoceros shrimp grow to a size of 3.5 to 4 centimetres, with the males being slightly smaller than the females. The narrow, slightly S-shaped body, which in females is slightly more arched at the abdomen, is transparent, sometimes milky, and shows a red longitudinal stripe. With their transparent body and filigree legs, red rhinoceros shrimp look very fragile. There are quite small antennae on the head and the scissors or pincers are also rather small. The tail tapers very sharply towards the end.
Red rhinoceros shrimp are demanding when it comes to keeping them. Their keeping is recommended for shrimp lovers who are already willing to put in more effort, especially when it comes to breeding this shrimp species. Red rhinoceros shrimp need sufficient swimming space, as they are very keen on swimming and are very active. The shrimp tank should therefore have a minimum size of 50 litres. As a very sociable shrimp species, they should only be kept in groups of at least ten animals. Curious, red rhinoceros shrimp not only explore the ground, but also plants, roots and stones.
Small rock caves, shards of clay, but also roots should offer them shelter. A dark, fine-grained or sandy substrate is visually advantageous. In their original habitat, red rhinoceros shrimps inhabit different habitats with brackish and fresh water. In the shrimp tank, they can be kept in freshwater with hard water values and slightly salted water. A salinity of approximately 15 g sea salt per litre is recommended. The optimum water temperature is 20 to 28°C and a pH value between 6.5 and 7.5. The carbonate value should be up to 11° dKH, while the total hardness of the water should be 8 to 15 dGH. Most aquarium plants tolerate hard fresh water that is slightly salted. However, red rhinoceros shrimp are not necessarily dependent on plant growth.
As omnivores, red rhinoceros shrimps have no special demands with regard to their food. They feed mainly on algae coverings, dead plant material and food remains which they find when searching the shrimp tank, especially the bottom ground. Frozen food or a special shrimp food is also accepted. In the shrimp tank, brown autumn leaves should be available to the red rhinoceros shrimp as a permanent food. Spinach or nettle sticks can also serve as an additional food source, as young plants are eagerly eaten by the animals. It is advisable to administer protein twice a week in the form of special protein food.
Red rhinoceros shrimp belong to the simple reproduction type, whose larvae are not born as fully developed young animals. The females regularly lay more than a thousand tiny eggs, which they release after a gestation period of about six weeks. Larvae that hatch in freshwater die after a few days, however. The offspring need brackish water for their development, which is why red rhinoceros shrimp cannot reproduce uncontrollably in freshwater aquariums. To breed red rhinoceros shrimp, females should be transferred to a rearing tank with hard, slightly salted water after two weeks of gestation to release the eggs. The mother can then be returned to the original shrimp tank.
The breeding tank is then salted very evenly until a value of half the seawater content is reached, which is typical for brackish water. After one month, regular water changes are carried out to gradually change the water back to hard, slightly salted fresh water. After about two months, the young shrimp can then be transferred to the actual shrimp tank. It is important that the salt content of the water is increased or decreased smoothly, as jumps that are too fast or too high will cause all larvae to die. During rapid and continuous larval growth, the feed size should be adjusted every few days. Thus the larvae should be fed with liquid plankton at the beginning, later on with powdered plankton and 100% spirulina powder. If the larvae are about 4 mm large, they can be fed with just hatched artemial larvae and very fine flake food.
Red rhinoceros shrimp can be easily socialised with other dwarf shrimp species, as they do not crossbreed with other shrimp species. With similar demands on water values, they can also be kept well in an aquarium with other peaceful creatures such as small fish species, crabs, crabs, mussels or snails. Pure species tanks exclusively with red rhinoceros shrimp are often not unusual.