Kingdom — Arthropoda.
Subphylum — Crustacea.
Class — Malacostraca.
Order — Decapoda.
Superfamily — Atyoidea
Family — Atyidae.
Genus — Caridina.
— Caridina cantonensis “Crystal Red” (CRS) — Crystal Red Shrimp, Red Crystal, Red Bee. “Red Bee shrimp”, “Crystal Red shrimp”, “Kristallrote Bienengarnele”. Asia. One of the most popular freshwater shrimps in aquarium hobby. Size: 2.5-3.0 cm. Among all other shrimp species, the Crystal Red stands out precisely for its coloration. The red-and-white coloration is the result of selective breeding, a variation of the “Bee” shrimp. Developed by Japanese breeders by crossing various Caridina cantonensis species originating from China. Due to selective inbreeding, these shrimps become more demanding to keep, and are more difficult to raise and breed.
This shrimp is not for beginners; keeping Red Crystals requires experience with shrimps, special care, and close attention to water parameters. This species demands much more attention and care than, for example, the Cherry Shrimp. There are many selective color morphs. Gradually, varieties of this shrimp mutation have been bred, differing in the shape and extent of red-colored areas. Unfortunately, because Red Crystals are an artificially bred form, their offspring often include fry with a “wild, natural coloration”. Red shrimps are classified according to their coloration. The higher the grade of the shrimp, the higher its price.
Minimum aquarium size is 50 liters, but the larger, the better. An optimal solution is to equip the breeding aquarium with a Hamburg mat filter and a powerful aerator. The filter intake must be protected with a sponge to prevent small shrimps from being sucked in. It is preferable to use a well-mulmed substrate — it may not look very pretty, but it is very beneficial.
The presence of stem plants is undesirable because when pruned, they sometimes release substances toxic to higher crustaceans into the water. As a proven greenery, most breeders use Java moss. Excellent results are also given by Monosolenium tenerum, as well as Marimo moss balls, which serve as great “pastures” for shrimps, including juveniles. There must be a sufficient number of hiding places for molting individuals and pregnant females.
These shrimps need lighting for no more than 14 hours. A heater is necessary in the aquarium, as shrimps will not breed, or will die, if the temperature is too high or too low. The temperature should be stable all year round, but below 27°C. The optimal temperature is 22-24°C. When exposed to water temperatures at the limit of tolerance, the shrimp reacts by fading in color. Shrimps cannot tolerate excessively high temperatures and will begin to die at the slightest error in maintenance, and they breed poorly. Raise or lower the temperature until the animals acquire a rich red-and-white color. Lower temperatures are preferred for successful breeding.
Soft and acidic water is ideal for breeding, whereas it is difficult to breed them in harder alkaline waters. Excessively soft water can cause sudden deaths due to calcium deficiency. Regular water changes are required. Constantly monitor ammonia and nitrite levels, check pH levels, and water purity is a mandatory requirement. Shrimps are very sensitive to ammonium and nitrite. pH 6.2-6.8, dH 4-6°, kH 1-2°; extreme values of these water parameters should be avoided. Minor deviations from these parameters do not negatively affect the shrimps. They are sensitive to sudden changes in water parameters.
This shrimp is quite delicate, and changes in water parameters negatively affect it. It enters a state of stress and may even perish. Since shrimps are very sensitive to water quality and react to the slightest deterioration by losing their white color, having filtration is highly desirable. As the grade of the Crystal Red shrimp increases, the water parameters for keeping them become even more important. Since genetic diversity is practically absent in this shrimp species, certain varieties belonging to the so-called “higher grade” of shrimps (determined mainly by coloration) are even more sensitive to water parameters.
Non-aggressive. Red Shrimps are more active at night, so it is recommended to feed 40% of the food in the evening. Along with algae, they also feed on carrion. Excess food and leaving it in the water for too long are undesirable. Overfeeding is a well-known cause of shrimp death and can also cause water quality issues. Fasting for 1-2 days does not harm shrimps. Food must contain sufficient nutrients and iodine. They are usually fed spinach, bloodworms, live marine algae, and algae tablets. Each breeding tank should contain Indian almond leaves and fallen leaves. They live for about 2 years depending on the maintenance temperature: a higher temperature shortens lifespan, while a lower one extends it.
Breeding Crystal Red shrimps is not overly difficult; crystals breed very easily. When kept in clean water and maintaining the required parameters, the offspring of the Crystal Red shrimp will be quite numerous. The main requirement is regular water changes and suitable parameters. To breed them, you need to create conditions in the aquarium as close to ideal as possible. Quality foods, optimal water parameters, and cleanliness in the home tank will allow the shrimps to remain active, delight you with numerous offspring, and successfully resist diseases.
Crystal Reds intended for breeding are best kept in large groups — this stimulates their reproduction. The starting population should be at least 20 individuals. Distinguishing a male from a female is only possible upon reaching sexual maturity. Females differ from males by having a more voluminous abdomen and a curved sub-abdominal section. Males are more slender. Females also have a so-called “saddle”, where future eggs are stored, though in well-colored shrimps it may be invisible. The saddle in a Crystal female is difficult to see due to the red stripe, because the eggs of Crystal Reds are also red. You might be lucky enough to see the eggs gathered in the saddle if they happen to be brown. Shrimps begin to breed at the age of 4-6 months and at a size of 2 cm.
Females carry eggs under their abdomen, and fully formed small shrimps hatch directly from the eggs. Eggs develop over 20-30 days, depending on the temperature. A female carries an average of 10-30 large brown eggs. When the incubation period comes to an end, the eggs become semi-transparent, and the eyes of the baby shrimps can be distinguished. Shrimps are born fully colored, just like their parents. Red stripes on a white background are visible immediately, but any specific coloration features that determine the shrimp’s grade become apparent only over time. However, offspring evaluation cannot be completed until they grow up.
Breeding CRS is quite challenging because selection must be carried out based on a fairly large number of traits, such as color saturation, the ratio of white to red, pattern, eye color, and limb color. Color quality depends on heredity. However, water quality also affects coloration (the presence of nitrates, nitrites, or ammonium in the water can cause the white color to fade). Stress can cause temporary fading of color, which recovers when the shrimp is placed in favorable conditions. Other factors have virtually no effect on shrimp coloration.
If you keep CRS for aesthetic purposes, you can mix different grades to the detriment of the resulting offspring. But if you are engaged in breeding, it is preferable to keep each grade separately. It would be wasteful to keep expensive “Mosura” shrimps with simple “C” grade shrimps, because over generations, you lose all “Mosura” qualities for any shrimp lines. And if you mix Black Crystal and Red Crystal, after a while you will have shrimps whose colors are neither red nor black, but orange-brown. However, keeping homogenous black and red crystals together is quite acceptable. Such crossbreeding will result in shrimps of both colors.
It is undesirable to keep white shrimps together with shrimps of other colors. Their crossbreeding can lead to a drop in color saturation in red and black crystals. At the same time, well-colored white shrimps can in some cases be used to improve the grade of red and black ones. Conversely, crossing well-colored red or black crystals with white ones can improve the white color of the latter.
It should be noted that most pure lines are difficult to maintain because their genetic pool is very limited. Only very experienced breeders with significant technical resources are able to achieve more or less acceptable survival rates and color quality. In addition, you must know and be able to recognize genetic defects in shrimps.
Compatible tankmates: CRS can interbreed with all varieties of Caridina cf. cantonensis (“Tiger”, “Red Tiger”, “Blue Tiger”, “Black Tiger”, “Orange Bee Shrimp”, CR/CB Shrimp), and there is also a possibility of crossbreeding with closely related species (Caridina serrata, C. maculata, C. breviata, C. venusta, C. meridionalis, C. tumida, etc.). Therefore, keeping them together is highly undesirable. It is also undesirable to keep high-grade shrimps together with low-grade ones, as this will lead to a decline in the quality of the higher-grade shrimps.
Caridina cantonensis “Black Crystal”.
Caridina cantonensis “Tiger”, “Black Tiger”, “Blue Tiger”, “Red Tiger”. 
