One of the true gems to be imported from the Western Coast of Africa, the African Angelfish is sought after for its remarkable beauty and adaptability to captive life. In the past, this species was rarely collected for the aquarium industry because of the location of its natural habitat. It is still one of the rarest Angelfish found in the market.

The African Angelfish is considered semi-reef and does best in aquariums utilizing Live Rock for filtration or decoration. It will spend much of its time picking algae and other organisms off of the rock.

Mandarin Fish are reef dwellers and slow moving. They are picky eaters and feed primarily on small crustaceans (such as Mysids, isopods, amphipods and benthic copepods) and other invertebrates with abundance on live rocks.

Mandarin Fish can be easily sexed with the male tends to be larger and more robust than the female. The male’s caudal and soft dorsal fins are larger and have more orange coloration on it’s face. The male has an elongated first dorsal spine, long enough to actually reach the base of the caudal peduncle when laid flat. Male mandarins can only be kept singly or with other females in an aquarium.

Mandarin Fish lack scales and have a thick, slimy, mucus coating on their bodies, that makes them resistant to parasitic skin diseases.

Due to their feeding habits and sensitive to water quality, mandarinfish are not suitable for the beginners as they are considered difficult to be kept. They usually do best in a well-established reef with peaceful, non-aggressive species maintained by the experienced reef keepers.

Harlequin Tuskfish is an incredible, vibrant coloration and otherworldly blue tusk-like teeth, unique-looking wrasse.  A hardy fish that acclimates well to aquarium life, makes a perfect specimen for the fish-only marine aquarium.  Read more at www.tfhmagazine.com

Seahorses

Seahorses form territories, with the males occupying about one square meter area of their habitat whereas the females can occupy a range of up to a hundred times of the area the males occupy.  These fish are well camouflaged by the greyish, brownish patterns that blends in well to their habitat background. However, they do turn bright colours during their social moments or when they are in unusual surroundings.

Seahorses do not have scales and a thin skin layer is stretched over a series of their bony plates arranged in rings throughout their body. Each species of the seahorses has a distinct number of rings and each of them has a distinct coronet on their head, like a human fingerprint. They swim upright but very poorly by fluttering their dorsal fin for propelling through the water, and pectoral fins for steering. Unlike fish, seahorses have no caudal fin. Their poor swimming characteristics find them resting in beds of sea grass or coral reefs, and with their prehensile tails wound around a stationary object most of the time. Seahorses have long snouts for sucking up food. Their eyes move independently of each other like a chameleon.

Seahorses afre finicky on their diet which comprised mainly tiny fish, small shrimp, and planktons. In the aquaria, you may feed them with frozen or live brine shrimps and mysis shrimps. Target feeding is recommended by dropping food close to their location.   

Male seahorses are have a brood pouch on their ventral side. The courting starts with several days’ affair between a pair when they discover mutual interest at the beginning of the the breeding season. Courtship is evident when both change colours, swimming side by side along each other, holding tails or doing some of their “pre-dawn dance”. When mating starts, the male pumps water through the egg pouch on his trunk which expands and cleaves open to display an appealing emptiness, and the female seahorse deposits their hundreds to thousands of eggs into the male’s pouch where the eggs are fertilized internally. The eggs are carried around by the male until they hatch and become fully-developed, miniature seahorses in the water. The male seahorse pregnancies last usually for two to three weeks.  The egg pouch provides oxygen and act as a controlled environment incubator.  The salinity of the water is regulated in the pouch for proper hatching.  Throughout the incubation period, his female mate usually visits him daily by swimming over for approximately 5 minutes of interaction. During this process, the pair changes colour and wheel around the sea grass fronds, and finally promenade by holding each other’s tails. 

The male undergoes muscular contractions to expel the fry from his pouch when they are ready, usually happens in the night. Seahorses do not care for their young once they are born, and the fry are vulnerable from the predators or strong ocean current. Survival rates are low and that the statistics are that less than five fry of every 1,000 borns manage to survive to adulthood in the wild. 

In captivity, seahorses should fare well if kept in a species aquarium to themselves, or with other compatible tank-mates. As seahorses are slow feeders, avoid putting them in an aquarium with fast and aggressive feeders.  The goby family of fish, shrimps and other bottom feeding creatures makes good tank-mates. In particular, avoid putting them together with eels, triggerfish, octopus, tangs, squid, and sea anemones.

Ideal water parameters would have a pH range between 8.0 to 8.3 and SG (specific gravity) between 1.021 to 1.024. Good water care with the aid of an efficient bio-filter is import to keep the ammonia and nitrite level nil.  Seahorses are not fussy about space and aquarium need not be too large.

A carefully setup seahorse aquarium with a stable and high quality environment will provide many hours of fascination.

Researchers at the Monterey Bay Aquarium Research Institute have solved the half-century-old mystery of a fish with tubular eyes and a transparent head. Ever since the “barreleye” fish Macropinna microstoma was first described in 1939, marine biologists have known that its tubular eyes are very good at collecting light. However, the eyes were believed to be fixed in place and seemed to provide only a “tunnel-vision” view of whatever was directly above the fish’s head.

A new paper by Bruce Robison and Kim Reisenbichler shows that these unusual eyes can rotate within a transparent shield that covers the fish’s head. This allows the barreleye to peer up at potential prey or focus forward to see what it is eating.

The barreleye fish, or Macropinna microstoma, has extremely light-sensitive eyes that can rotate within a transparent, fluid-filled shield on its head. The fish’s tubular eyes are capped by bright green lenses. The eyes point upward when the fish is looking for food overhead. They point forward when the fish is feeding. The two spots above the fish’s mouth are olfactory organs called nares, which are analogous to human nostrils.

Deep-sea fish have adapted to their pitch-black environment in a variety of amazing ways. Several species of deep-water fishes in the family Opisthoproctidae are called “barreleyes” because their eyes are tubular in shape. Barreleyes typically live near the depth where sunlight from the surface fades to complete blackness. They use their ultra-sensitive tubular eyes to search for the faint silhouettes of prey overhead.

Although such tubular eyes are very good at collecting light, they have a very narrow field of view. Furthermore, until now, most marine biologists believed that barreleye’s eyes were fixed in their heads, which would allow them to only look upward. This would make it impossible for the fishes to see what was directly in front of them, and very difficult for them to capture prey with their small, pointed mouths.
Robison and Reisenbichler used video from MBARI’s remotely operated vehicles (ROVs) to study barreleyes in the deep waters just offshore of Central California.

At depths of 600 to 800 meters (2,000 to 2,600 feet) below the surface, the ROV cameras typically showed these fish hanging motionless in the water, their eyes glowing a vivid green in the ROV’s bright lights. The ROV video also revealed a previously undescribed feature of these fish–its eyes are surrounded by a transparent, fluid-filled shield that covers the top of the fish’s head.

Most existing descriptions and illustrations of this fish do not show its fluid-filled shield, probably because this fragile structure was destroyed when the fish were brought up from the deep in nets. However, Robison and Reisenbichler were extremely fortunate–they were able to bring a net-caught barreleye to the surface alive, where it survived for several hours in a ship-board aquarium. Within this controlled environment, the researchers were able to confirm what they had seen in the ROV video–the fish rotated its tubular eyes as it turned its body from a horizontal to a vertical position.

This face-on view of a barreleye shows its transparent shield lit up by the lights of MBARI’s remotely operated vehicle Tiburon. As in the other photos, the two spots above the fish’s mouth are are olfactory organs called nares, which are analogous to human nostrils.

In addition to their amazing “headgear,” barreleyes have a variety of other interesting adaptations to deep-sea life. Their large, flat fins allow them to remain nearly motionless in the water, and to maneuver very precisely (much like MBARI’s ROVs). Their small mouths suggest that they can be very precise and selective in capturing small prey. On the other hand, their digestive systems are very large, which suggests that they can eat a variety of small drifting animals as well as jellies. In fact, the stomachs of the two net-caught fish contained fragments of jellies.

After documenting and studying the barreleye’s unique adaptations, Robison and Reisenbichler developed a working hypothesis about how this animal makes a living. Most of the time, the fish hangs motionless in the water, with its body in a horizontal position and its eyes looking upward. The green pigments in its eyes may filter out sunlight coming directly from the sea surface, helping the barreleye spot the bioluminescent glow of jellies or other animals directly overhead. When it spots prey (such as a drifting jelly), the fish rotates its eyes forward and swims upward, in feeding mode.

Barreleyes share their deep-sea environment with many different types of jellies. Some of the most common are siphonophores (colonial jellies) in the genus Apolemia. These siphonophores grow to over 10 meters (33 feet) long. Like living drift nets, they trail thousands of stinging tentacles, which capture copepods and other small animals. The researchers speculate that barreleyes may maneuver carefully among the siphonophore’s tentacles, picking off the captured organisms.

The barreleye fish’s eyes rotate to help the fish keep its “eyes on the prize,” while its transparent shield protects the fish’s eyes from the siphonophore’s stinging cells. MBARI researchers speculate that Macropinna microstoma may eat animals that have been captured in the tentacles of jellies, such as this siphonophore in the genus Apolemia. The “head” of the siphonophore (at right) pulls the animal through the water, its stinging tentacles streaming out like a living drift net.

Robison and Reisenbichler hope to do further research to find out if their discoveries about Macropinna microstoma also apply to other deep-sea fish with tubular eyes. The bizarre physiological adaptations of the barreleyes have puzzled oceanographers for generations. It is only with the advent of modern underwater robots that scientists have been able to observe such animals in their native environment, and thus to fully understand how these physical adaptations help them survive.

Source: John Chapin, The Cutting Edge News

It reaches a length of approximately 3.2″ (8 cm) in the wild, but is considerably smaller in aquarium bred specimens that rarely exceed 2″ (5 cm). Ocellaris is a hardy, long-lived clownfish that is excellent for the beginner hobbyist. It lives harmoniously with other non-predatory species and is best in aquariums with the presence of anemones such as Heteractis magnifica and Stichodactyla gigantea. It can become aggressive towards others of its species. A good suggestion would be to keep a mated pair of Ocellaris in the same aquarium, or as a school introduced to the aquarium when they are very young.

There is no external characteristics to differentiate a male and female and are sexually immature when hatched, i.e., the fry do not have a pre-determined sex. The fry develop into males and females depending on the hierarchy of the school. Ocellaris exhibits parental instincts and will pair off to lay the orange coloured eggs along the base of the host anemone, which serves the purpose of protecting the eggs. The parents will defend the eggs and will occasionally fan them.  The eggs will hatch after eight days. Without proper preparation, rearing the fry is challenging in an aquarium and demands proper preparation of the water condition and care.  The fry should be removed from the harm of any predators and their parents after hatching.  

Ocellaris feed mostly meaty foods and frozen herbivore preparations. Flake food, brine shrimp and mysis shrimp are also readily accepted. It is a good idea to rotate the types of food to prevent the fish from becoming picky.