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Maximum size : 15 cm

Rainbow Shark - Epalzeorhynchos Frenatum : Complete Fish Profile & Care Guide

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Rainbow Sharks, (Epalzeorhynchos Frenatum) are undoubtedly some of the most visually striking fish to grace the aquarium scene. However, despite their impressive beauty, these creatures are known to exhibit aggression towards one another if kept together in a tank. Threat displays and fighting, which may involve head-and-tail butting, as well as biting, are not uncommon. Larger Rainbow Sharks can become particularly territorial, relentlessly chasing smaller individuals until they perish or drive other fish from their domain. This behavior can also increase the likelihood of the fish jumping out of the tank. While juveniles tend to be more timid and spend considerable time concealing themselves, this species ' aggressive tendencies toward their own kind make them less suitable for inexperienced aquarists. Nonetheless, Rainbow Sharks can coexist harmoniously with Barbs and Rainbowfish, which tend to inhabit the upper and middle sections of the tank. Other compatible tankmates include Danios, Loaches, Plecos, Rasboras, and Gouramis. While some larger freshwater Shrimp species can live alongside Rainbow Sharks, it is essential to note that any fry or eggs may become a meal for these creatures. Smaller, more retiring fish should be avoided, as Rainbow Sharks may harass and intimidate them into leaving their territory. Rainbow Sharks are relatively unpretentious when it comes to decor, provided that adequate cover is available. Moreover, they should not cause any harm to softer-leaved plants. To simulate their natural habitat, it is recommended to construct an aquarium that mimics a flowing river, with a substrate composed of rocks of varying sizes, gravel, and larger water-worn boulders. The addition of driftwood roots and branches, along with hardy aquatic plants grown attached to the decor, can further elevate the aquarium 's aesthetics. Rainbow Sharks, like many fish indigenous to running water, exhibit low tolerance to organic waste buildup, and require an environment with ample dissolved oxygen and moderate water flow to flourish. The Rainbow Shark boasts an elongated body that may appear black, dark blue, or bright blue. Its pointed snout and flat abdominal area are among its distinctive features. The fish 's fins exhibit a range of hues, from red to orange-red, and a characteristic brief stripe extends from the gill cover, eye, and mouth. Compared to females, male Rainbow Sharks have thinner bodies with black lines along the tail fins and more vibrant coloration. For enthusiasts seeking an alternative to the standard Rainbow Shark, the Albino Rainbow Shark presents a captivating option. While it shares the characteristic orange-red fins, its creamy-white body sets it apart from its more common counterpart.

Rainbow Shark Photos

Sexual Dimorphism

Discerning between male and female Rainbow Sharks is a task of moderate simplicity. Typically, males are distinguishable by their vibrant red or orange fins, which tend to be more pronounced than those of the female counterparts. Additionally, the males of this species possess slender grey lines on their tail fins, a feature that is absent in females. Female Rainbow Sharks, on the other hand, exhibit more rounded bellies and generally appear thicker in comparison to their male counterparts. It is worth noting that these distinguishing characteristics only become evident as the fish matures, as juvenile Rainbow Sharks do not exhibit any significant sexual dimorphism.

Quick Facts

Scientific NameEpalzeorhynchos Frenatum
Year Described1934
Other NamesRed-Finned Shark, Ruby Shark, Green Fringelip Labeo, Whitefin Shark, Whitetail Shark.
OriginsThailand Malaysia Laos Myanmar
Max Size15 cm
Aquarium LevelBottom - Middle
Best kept asLoners
Lifespan5-8 years

Water Parameters

Water TypeFreshwater
PH6.5 - 7.5
73 - 79
22.8 - 26.1

Natural habitat

Rainbow Sharks are native to Thailand, Malaysia, Laos, and Myanmar in Southeast Asia. In their natural environment, Rainbow Sharks thrive in clean, warm, freshwater rivers with plenty of plankton and sandy bottoms. It 's within these tranquil waters that they make their home, scouring the riverbed for food and shelter. Interestingly, Rainbow Sharks are known to migrate into floodplains, flooded fields, and forests during durations of heavy rain pour or flooding. This remarkable adaptation allows them to thrive even in the face of changing conditions, making them a truly unique and fascinating species. Recreating the perfect environment for Rainbow Sharks in your home aquarium requires a bit of effort, but the results are well worth it. With their vibrant colours and playful personalities, Rainbow Sharks are an excellent addition to any aquatic community. So why not join us on a journey to Southeast Asia 's freshwater rivers and discover the wonders of Rainbow Sharks for yourself?

How to breed the Rainbow Shark

In their natural habitat, Rainbow Sharks engage in a mesmerizing mating ritual that typically occurs between the months of October and November, just as they reach sexual maturity. However, the exact timing of their amorous exploits can be influenced by a variety of factors, including shifting seasons, temperature fluctuations, and changes in daylight hours. During the mating process, the female Rainbow Shark will release her eggs, which are then immediately fertilized by the male as he sprays them with his milt. Within approximately one week, the eggs will hatch, revealing the newest generation of these captivating creatures. While breeding Rainbow Sharks may seem like a thrilling endeavor for aquarium enthusiasts, the unfortunate reality is that it is an incredibly challenging feat to accomplish. To date, there is no recorded evidence of successful breeding of these creatures in a home aquarium. However, it is worth noting that large quantities of Rainbow Sharks are bred successfully in commercial farms throughout Southeast Asia. Despite the difficulties associated with breeding Rainbow Sharks, observing these beautiful creatures in their natural habitat during the mating season is a truly awe-inspiring sight to behold.

Diet & feeding

Rainbow Sharks exhibit a relatively non-discriminatory attitude when it comes to their dietary preferences, consuming most items as long as they sink to the bottom of the tank. To ensure optimal health and immune function, it is recommended to provide Rainbow Sharks with a diversified diet. This can be accomplished by offering them an assortment of algae wafers or tablets, insect larvae, frozen or live food, and zooplankton. Additionally, blanched vegetables such as spinach, lettuce, and peas can serve as a nutritious and enjoyable supplement to their regular feeding routine.

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