[Ebook] Encyclopedia of Aquarium & Pond Fish – Directory of Marine Fish – Groupers and Grunts

Directory of Marine Fish

Groupers and Grunts

These colorful fish are not especially difficult to maintain in aquarium surroundings, but they will grow to a large size and so will eventually require a spacious setup. This needs to be taken into consideration from the outset, since it is not easy to find new homes for such fish once they have outgrown the average-sized home aquarium. While some groupers and grunts are shoaling fish, others tend to seek out suitable retreats on the reef where they can lurk. Sexing can be difficult, since many species show hermaphrodite characteristics and are able to change gender to suit their environment.

Porkfish (Anisotremus virginicus)

• ORIGINS: Occurs throughout the Caribbean region, from Florida down to the northern coast of South America.
• SIZE: 12 in (30 cm).
• DIET: Fresh or thawed meat-based foods.
• WATER: Temperature 77–79°F (25–26°C); alkaline (pH 8.1–8.3) with SG 1.021–1.024.
• TEMPERAMENT: Preys on invertebrates

Porkfish are members of the grunt family— a name derived from their ability to produce sounds that resemble the grunts of pigs. They have a long, steep forehead and large eyes. Juveniles differ markedly from the adult seen above, having black stripes running the length of their bodies and a distinctive black blotch on the caudal peduncle.

Panther Grouper (Cromileptes altivelis)

• ORIGINS: East Africa across the Pacific to Japan, Australia’s Great Barrier Reef, and Vanuatu.
• SIZE: 27 in (70 cm).
• DIET: Dried and thawed marine foods.
• WATER: Temperature 77–79°F (25–26°C); alkaline (pH 8.1–8.3) with SG 1.021–1.024.
• TEMPERAMENT: Will prey on smaller companions.

The spotted appearance of these distinctive fish becomes more pronounced with age. Panther Groupers have prodigious appetites and grow fast, so it is important that the filtration system in their aquarium is effective enough to handle the resulting volume of waste. Loss of appetite in this species often signals a deterioration of water quality, in which pH can drop markedly.

Swiss Guard Basslet (Liopropoma rubre)

• ORIGINS: Caribbean region, from Florida down to the Venezuelan coast.
• SIZE: 4 in (10 cm).
• DIET: Fresh and thawed marine foods, as well as flake.
• WATER: Temperature 77–79°F (25–26°C); alkaline (pH 8.1–8.3) with SG 1.021–1.024.
• TEMPERAMENT: Mixes well.

These small, attractive fish are ideal for a mixedspecies aquarium, where they tend to occupy the area from midwater downward. They are adept at hiding away in nooks and crevices, proving to be rather shy by nature. Their unusual common name reflects the fact that their coloration resembles the uniform of the Papal Swiss Guard based in Vatican City.

Blacktip Grouper (Epinephelus fasciatus)

• ORIGINS: Ranges eastward from the Red Sea, via the Indo-Pacific region, to Oceania.
• SIZE: 14 in (35 cm).
• DIET: Thawed and dry marine foods.
• WATER: Temperature 77–79°F (25–26°C); alkaline (pH 8.0–8.3) with SG 1.021–1.024.
• TEMPERAMENT: Do not house with invertebrates.

The appearance of these groupers, or Rock Cod as they are also known, can be very variable. Some individuals show more numerous or extensive reddish-orange body markings and smaller white patches than others. However, the presence of black tipping along the dorsal fin is a consistent feature. Blacktip Groupers spend most of their time on or near the base of the aquarium, where they also feed. They are solitary by nature.

Shy Hamlet (Hypoplectrus guttavarius)

• ORIGINS: Found in the Caribbean region, from Florida down to the coast of South America.
• SIZE: 6 in (15 cm).
• DIET: Fresh or thawed marine foods.
• WATER: Temperature 77–79°F (25–26°C); alkaline (pH 8.0–8.3) with SG 1.021–1.024.
• TEMPERAMENT: Retiring and peaceful.

The back of this hamlet is dark in some specimens but a much bluer shade in others. These fish need nooks and crannies in the aquarium where they can hide, although they do become bolder once they are established in their quarters. It is possible to breed Shy Hamlets in home aquariums. Amazingly, each fish is a hermaphrodite, possessing both male and female sex organs, so any two Shy Hamlets should be able to mate successfully.

Blue Hamlet (Hypoplectrus gemma)

• ORIGINS: The Caribbean region, from the coast of Florida down to northern South America.
• SIZE: 5 in (13 cm).
• DIET: Thawed marine foods.
• WATER: Temperature 77–79°F (25–26°C); alkaline (pH 8.0–8.3) with SG 1.021–1.024.
• TEMPERAMENT: Predatory.

The blackish upper and lower edges on the caudal fin distinguish this species from the much rarer Indigo Hamlet (H. indigo). Blue Hamlets are predatory by nature and cannot be kept safely with smaller companions. They are more sensitive to water quality than their larger relatives; the total nitrate reading should not be allowed to rise above 10 ppm. For this reason, the tank’s filtration system should include a protein skimmer

Blue-Spotted Grouper (Cephalopholis argus)

• ORIGINS: Ranges from the Red Sea throughout the Pacific Ocean.
• SIZE: 20 in (50 cm).
• DIET: Thawed marine foods.
• WATER: Temperature 77–79°F (25–26°C); alkaline (pH 8.0–8.3) with SG 1.021–1.024.
• TEMPERAMENT: Will prey on smaller fish.

The striking coloration of these groupers has made them popular with marine aquarists, but as in the case of similar species, they are likely to grow rapidly and can reach a large size. This demands both a correspondingly large aquarium and an efficient filtration system. Any loss of color is usually a sign of deteriorating water quality; this needs to be monitored closely. Blue-Spotted Groupers are not particularly active fish, seeking out suitable retreats near the bottom of the aquarium, where they can lurk and wait for food. Their attractive patterning of black-ringed blue spots extends over the fins as well as the body, but the distribution of spotted markings differs between individuals. The spots appear to glitter when caught by the light.

INTIMIDATING GAPE

Groupers are not the most active fish on the reef, but they are still effective predators, thanks to their quick reflexes, large mouths, and fearsome array of teeth, as visible in this Marbled Grouper (Epinephelus polyphekadion). The spotted patterning helps to conceal them as they lie in wait for small fish or invertebrates to swim within reach. A grouper will also open its mouth wide to intimidate rivals. Some groupers reach a huge size on the reef, with relatives of the Blacktip Grouper (see top left) weighing 1,000 lb (450 kg) and measuring nearly 10 ft (3 m).

[Ebook] Encyclopedia of Aquarium & Pond Fish – David Alderton (Photo by Max Gibbs)