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White-streaked Grouper

(Epinephelus ongus)

White-streaked Grouper
  • Reef SafetyFish Only
  • Care LevelAdvanced
  • TemperamentHighly Predatory
  • Diet TypeCarnivore
  • Role in AquariumPredator
Native RangeIndo-Pacific, including the Red Sea, Indonesia, and the Philippines
Species Description
Scientific NameEpinephelus ongus
Common NameWhite-streaked Grouper
Species GroupSea Basses & Groupers
Max Fish Length20 in (51 cm)
Min Aquarium Size200 gal (757 L)

Overview

  • Found in the Indo-Pacific region, including coral reefs and coastal waters.
  • Recognized by its dark brown body covered with small white spots.
  • A carnivorous species known for its ambush hunting behavior.
  • Typically inhabits reef crevices and rocky outcrops for shelter.

Feeding

  • Predatory diet primarily consisting of small fish and crustaceans.
  • Readily consumes live prey, frozen seafood, and meaty pellets.
  • Occasionally supplements diet with squid and cut fish pieces.
  • Should be fed a protein-rich diet to maintain health and vibrant coloration.

Habitat

  • Typically found in rocky reefs and coral structures.
  • Prefers areas with ample hiding spots to ambush prey.
  • Requires a spacious aquarium with stable water conditions.
  • Thrive in environments with moderate water movement.

Fish Care

  • Optimal water temperature: 74-82°F (23-28°C).
  • Ideal pH level: 8.1–8.4, with a specific gravity of 1.025–1.026 (about 33–35 ppt).
  • Requires a large aquarium due to its potential growth size.
  • Can be territorial, especially towards similar-sized fish.
  • Regular water changes and strong filtration are essential.

Compatibility

  • Best suited for tanks with similarly sized or larger tank mates.
  • May exhibit aggressive behavior towards smaller fish.
  • Compatible with other groupers, eels, and large wrasses.
  • Solitary nature means it does well as the dominant predator in the tank.

Aquarium Behavior

  • A nocturnal predator, often hiding during the day.
  • Prefers to stay near rock crevices and ledges.
  • Will aggressively defend its territory if threatened.
  • Exhibits ambush-hunting behavior, striking prey swiftly.

Frequently Asked Questions

What other names does the White-streaked Grouper have?

Other common names include specklefin grouper, lace-finned rock-cod, wavy-lined rock-cod, white-speckled grouper and white-spotted rock-cod.

How big does it get?

Our page lists about 20 in (51 cm).

What size tank does it need?

Our page recommends at least 200 gallons (757 L) and rates it for fish-only aquariums.

What does it eat in the wild?

It feeds on crustaceans and small fishes.

Can it live with small fish or shrimp?

No. It is highly predatory, and its wild diet of crustaceans and small fish means small tankmates and shrimp are likely to be eaten.

What is its natural habitat?

Adults live on inner coastal and lagoon reefs, in ledges and caves, and are usually found deeper than about 66 ft (20 m).

Can it live in brackish water?

It is also found in brackish waters as well as marine reefs.

Is it a shy fish?

It is cryptic and solitary, so give it caves and ledges to shelter in.

What should I feed it?

Our page lists it as a carnivore, so feed meaty marine foods such as fish, shrimp and squid.

Is it a good beginner fish?

No. Our page rates it for advanced keepers because of its size and predatory habits.