Feeding the Mandarin Fish

For so many aquarists, the green mandarin fish (Synchiropus splendidus) is a must-have species. Its endearing personality, exquisite finnage, and intense coloration rarely fail to impress. Given these highly desirable traits, it has for long been among the most popular marine aquarium fishes. Thus, many thousands of specimens of this species are sold in the ornamental fish trade each year. Most of these are wild-caught. This is unfortunate, as individuals have a rather poor record of survivability compared to captive-raised individuals.

The Survival Dilemma: Wild-Caught vs. Aquacultured Mandarin Fish

Understanding the feeding challenges and survival rates between wild-caught and aquacultured Mandarin Fish is crucial for both prospective and current aquarium owners.

The Perils Facing Wild-Caught Mandarin Fish

Wild-caught Mandarin Fish face a series of threats that significantly lower their survival rate compared to their captive-bred counterparts. The use of mini-spears for capturing these fish often results in serious internal injuries or infections, severely compromising their health.

The Impact of Transportation

Upon being caught, wild mandarins typically undergo a period of fasting during transportation. This practice frequently leads to malnourishment, and despite receiving dedicated professional care upon arrival, many are too weakened to recover, making their survival uncertain.

Opting for Aquacultured Mandarin Fish: A Wise Choice

Given these challenges, aquacultured Mandarin Fish emerge as the preferred choice for aquarium enthusiasts. Choosing cultured livestock is not only ethical but also practical, as these fish are more resilient and adaptable due to their controlled rearing environment.

Dietary Distinctions: A Key Difference

Among the many benefits of opting for aquacultured Mandarin Fish, the most notable is the significant difference in their diet and feeding habits. Aquacultured mandarins are more accepting of various foods and generally display healthier eating patterns, providing aquarium owners with a rewarding and less stressful experience.

Distinctions in Eating Habits: Wild vs Captive-Bred Mandarin Fish

Wild-caught Mandarin Fish often display reluctance in accepting new types of foods and might solely depend on live feeds. Unfortunately, some may never acclimatize to the aquarium’s feeding environment, succumbing within a short time frame.

Adapting to New Foods: Challenges with Wild-Caught Specimens

Wild-caught specimens may eventually initiate feeding but typically refuse anything other than live foods. There’s also a risk with some individuals never resuming feeding in the aquarium, leading to their premature demise.

Flexibility in Captive-Bred Mandarin Diets

In contrast, aquacultured Mandarin Fish, which are raised in captivity, are less finicky about their diet. These captive-bred specimens often readily accept frozen food items, including cyclops, small mysis, or baby brine shrimp. Some may even be pre-conditioned to consume prepared foods like fish pellets upon arrival.

Extra Calories but Not a Substitute

While the consumption of prepared or frozen foods provides aquacultured Mandarin Fish with additional calories, it doesn’t eliminate the necessity for continuous availability of live feed like copepods.

Unique Dietary Adaptations of Mandarin Fish

Mandarin Fish possess special adaptations, from mouth shape to digestive function, designed for feeding on microcrustaceans, primarily copepods and amphipods.

Diversity in Natural Diet

Studies have shown that while Mandarin Fish consume a variety of small creatures, including baby snails, copepods and amphipods are the staples in their diet, providing the majority of their nutritional intake.

Continuous Feeding: A Survival Imperative

Due to the tiny size of their prey, Mandarin Fish need to consume a large quantity to meet their dietary needs. Whether in the wild or in captivity, these fish commence hunting at dawn and continue until dusk, necessitating constant feeding for both wild and captive-bred specimens.

Challenges of Sustaining Pod Populations in Captivity

In captivity, heavy predation by even a single mandarin can significantly reduce pod populations. Even with periodic additions of new pods to the system—which is a recommended practice—the population might not remain dense enough to support a mandarin over the long term.

The Consequence of Depleting Pod Numbers

As pod numbers in the tank decrease, mandarins must expend more time and energy to locate food. When pod numbers critically diminish, mandarins struggle to meet metabolic needs and start showing signs of starvation.

Recognizing Signs of Starvation in Mandarin Fish

General lethargy and noticeable loss of body mass are telltale signs of starvation in mandarin fish. Whether aquaculture-raised or wild-caught, starving mandarins exhibit a sunken belly and long indentations on each side of their back.

Importance of Supplemental Feeding for Mandarin Fish

Supplementing with frozen or prepared foods can be crucial for the health of Mandarin Fish in captivity. Offering additional bites of frozen brine shrimp, for instance, can provide a much-needed boost to a newly arrived and very hungry mandarin.

Utilizing Frozen or Prepared Foods

Used regularly, supplemental foods like frozen brine shrimp can help keep both captive-bred and recently acquired mandarins healthy and well-nourished over the long run. This practice not only supports their immediate dietary needs but also ensures they receive all the necessary vitamins and minerals for optimal health.

Considerations in Supplemental Feeding

However, due to the mandarin fish’s small stomach and inability to gorge, as well as its constant need to eat, it’s essential to consider these frozen or prepared foods as snacks rather than main meals. This approach will help maintain the fish’s health while accommodating its unique dietary restrictions and needs.

Ensuring a Balanced Diet for Mandarin Fish

While supplemental foods offer significant benefits, they should only constitute a small fraction of the Mandarin Fish’s diet. Pods remain the principal food source for mandarins, even in captivity.

Maintaining Pod Populations for Feeding

Aquarium keepers should maximize feeding opportunities for Mandarin Fish by regularly introducing a variety of live microcrustaceans into the system. Products like live Harpacticoid (bottom-dwelling) copepods or Wild Plankton Mix are ideal choices for maintaining healthy pod populations.

Observing Tank Conditions for Pod Visibility

A helpful tip for keepers: if you struggle to see pods on the tank glass, your Mandarin Fish is likely having the same issue. Ensuring visible and accessible pods is crucial for the fish’s successful feeding.

Introducing Live Food Varieties

Occasionally offering different types of live foods, such as high-quality Maine Amphipods, can not only diversify the Mandarin Fish’s diet but also provide valuable behavioral enrichment, enhancing their overall well-being and activity levels.

Key Considerations for Successful Mandarin Fish Feeding

Successfully feeding both wild-caught and captive-bred Mandarin Fish is a challenge. A combination of continuous live pod supply, frequent supplemental feedings, and training for acceptance of frozen or prepared foods is the best strategy.

Selecting the Right Mandarin Fish

To increase the chances of success, consider starting with a robust, tank-conditioned, disease-free Mandarin Fish that already has a good appetite. Choosing an individual that is eating well increases the likelihood of enjoying your vibrant and healthy Mandarin Fish for many years.