Maintaining the ideal temperature in a fish tank is crucial for sustainable breeding.
However, this temperature requirement varies for different types of species, and the protagonist of today’s guide is the Red Cherry Shrimp! One of the most popular invertebrates among fishkeepers, cherry shrimps are native to Taiwan but scattered across the fresh waters in Asia.
Despite their fiery red bodies, cherry shrimps exhibit a peaceful temperament. Plus, they do not require much care and are compatible with most shrimps and snails.
However, for breeding cherry shrimp, temperature plays a crucial role. Let’s take a look at the different cherry shrimp temperature ranges suitable for their development and reproduction.
What is the Best Temperature for Cherry Shrimp?
Quick answer? – 74 °F (23°C)
Interestingly, shrimps are poikilothermic, which makes their body temperature vary according to the external temperature. In turn, their body temperatures determine the quality of their life. From breeding to their daily movements- all of these aspects are heavily dependent on the shrimps’ body temperature.
Speaking of the ideal temperature, anything between 68-74°F is suitable for maximum cherry shrimp keeping. However, thanks to their adaptive nature, shrimps can survive and thrive in most temperature ranges and external conditions. But on one condition- no predators!
What Happens If the Water Becomes Too Hot?
Keeping cherry shrimps in higher temperatures (71°F and above) increases their breeding rate. In fact, their growth hits an all-time high at 77°F. If the water is warmer than 77°F, there won’t be any more noticeable changes in the growth rate.
However, keep in mind that warmer water speeds up their growth and life cycle. While this may be advantageous for breeders, others must note that increasing the temperature also shortens their lifespan.
Since they’ll be breeding rapidly, the risk of failed molts, bacterial infections, and aquarium pests like Planaria also rises.
What Happens If the Water Becomes Too Cold?
As you may have already guessed, the growth rate of cherry shrimps is slowed down in cold water (below 71°F). Shrimplets, sub-adults, and adults will grow at a slower pace, thereby decreasing the speed of breeding. By further lowering the temperature, you can even stop the act of breeding altogether.
Cherry Shrimp Breeding Temperature
Cherry shrimps are one of the easiest species to breed. Along with a heavily planted aquarium and high protein food, cherry shrimps will need a warm, tropical environment for proper breeding.
Scientists from Turkey have studied how temperature affects the sex ratios of red cherry shrimp. The results show that the higher temps lead to a higher male ratio in hatchlings.
They kept three tanks at each temperature: 68°F(20°C), 73°F (23 °C), and 78°F(26 °C) while data was recorded for each temperature, include survival rate, egg quantity, and hatching time. A comprehensive experiment was conducted at three temperatures.
Temperature Affects Sex Ratio In Red Cherry Shrimp
The sex of the cherry shrimps depends on genetics and the external environmental conditions of the aquarium. The latter is further determined by the temperature and photoperiod, both of which play crucial roles in maintaining gametogenesis and other biological processes.
The sex ratio (female/male) of N. davidi reared at 20, 23 and 26ºC. One Way Analysis of Variance and Holm-Sidak All Pairwise Multiple Comparison Procedure. Error bars indicate ±SD. Different letters indicate significant difference (P < 0.05).
There are some interesting findings in this study. It seems that the sex ratio(female/male) changes directly related to temperature, with 80% at 68°F(20°C) and approximately 50% at 73°F (23 °C) but drastically decreasing down to 18% at 78°F(26 °C). This is why in sex-dependent selective cherry shrimp breeding, we should take into consideration the temperature.
We also found other data of the sex ratio (f/m) which was not shown on the above chart:
- 60 – 40 at 24 ºC (75 ºF)
- 55 – 45 at 28 ºC (82 ºF)
- 51 – 50 at 32 ºC (89 ºF)
The warmer temperatures (28 ~ 32°C) may benefit fish breeders, but it increases the shrimps’ metabolism to an exponential rate. This is detrimental to their growth and development.
Further, hot water at 32 ºC (89 ºF) makes it difficult for female shrimps to carry their eggs, and sometimes the eggs do not get “berried” at all.
According to the study, this tendency is credited to the natural survival instincts of the cherry shrimps. For instance, the rainy season lowers the water temperature and increases the chances of finding food and nutrition. Naturally, the shrimp will grow and reach their optimum health, and the number of females will increase.
Temperature Affects the Egg (Embryonic) Development
The number of eggs produced by adult N. davidi at 20, 23 and 26ºC. Vertical bars indicate stand-ard error of the mean. Significant difference at 20 ºC (**P <0.01).
The experiment was conducted at three different temperatures, they found the egg produce and larval output speed up at 26ºC comparing the lower experimental temperatures. A female cherry shrimp can produce a maximum of 45 eggs.
From the graph, it can be seen that the hatching period is accelerated with higher temperatures. The average incubation stage lasts about 30 days, depending on the temperature.
The hatching duration of N. davidi reared at 20, 23 and 26ºC. Kruskal-Wallis One Way Analysis of Variance and Tukey All Pairwise Multiple Comparison procedure. Vertical bars indicate standard error of the mean. Different letters in-dicate significant difference (P < 0.01).
A high-temperature range (80-90ºF) creates stress among female shrimps and affects ovarian maturation.
Temperature Affects the Survival Rates of the Shrimplets
The mean survival of N. davidi reared at 20, 23 and 26ºC. Kruskal-Wallis One Way Analysis of Variance and Tukey All Pairwise Multiple Comparison procedure. Vertical bars indicate standard error of the mean. Significant difference at 20ºC (**P <0.01).
Although the survival rates of the shrimplets are not directly affected by the temperature range, higher temperatures have resulted in low survival. This may be because of faster hatching, high energy consumption, and deformities in embryos.
Hence, fishkeepers must be extra cautious while tweaking the water temperature to ensure optimum survival.
Temperature Zones for Cherry Shrimp
Blue Temperature Zone (68-71ºF)
Lower temperature slows the growth rate and sexual maturity in cherry shrimps. As a result, egg maturation is delayed, and reproduction does not take place. However, due to the delayed sexual maturity, cherry shrimps are able to grow much larger.
Green Temperature Zone (73-79ºF)
This temperature range ensures ideal conditions for the eggs to develop and survive. Thus, the individual health and coloration of cherry shrimps also improve.
Red Temperature Zone (80-89ºF)
While warmer water ensures faster sexual maturity and breeding, it also results in a high mortality rate and low egg survivability. It further results in temperature stress, which may affect coloration.
And despite growing in terms of sexual maturity, cherry shrimps bred in warm water do not show much physical growth. Thus, they’re much smaller in size when compared to those bred in cold water.
Therefore, although the growth speed increases with the rise in temperature, their health and survival rate begin to decline on reaching the upper thermal limit of tolerance.
Overall, it is necessary to change the temperature range of the aquarium according to the breeding and life cycle of cherry shrimps.
Even a slight change in the water temperature can drastically affect the sex ratio and survival of the shrimp colony, embryonic development, coloration, and more. Hence, it is recommended that you tweak the temperature during the pre-breeding period for a month or so.
Once the offsprings hatch successfully, you can go back to the ideal temperature range to ensure healthy development and survival.