The personable Whitespotted Grouper is a more manageable size than many other groupers, and will reward you with years of companionship if you provide a large tank!

The Whitespotted Grouper starts out as a little brown juvenile with white spots and yellowish orange pectoral fins at 2.4.”  At 3.9,” many of the spots become more oval and elongated.  Adults are also brown, with some round spots, but more white lines that form irregular rows.  They also can intensify their color, forming large white blotches all over their bodies.  Their pelvic and pectoral fins are longer and powerful, allowing them to strike at prey in an instant.  Whitespotted Groupers grow to 11.8” (30 cm) and groupers are known to live from 9 to 37 in the wild, possibly longer in captivity with proper care.   They are a great beginner’s fish with the correct tank size.

Due to their camouflage appearance, Epinephelus or Spotted Groupers can sit very still and be almost invisible to their prey.  Also, ,many fish look at other fish and use the positioning of their eyes to determine if they need to run (closer together and near the top if they are a predator) or if they are a safe herbivores (eyes are positioned more on the sides).  This is the advantage the Whitespotted Grouper has, since their overall dark appearance and white spots make the location of their eyes difficult to find!  In the wild, the Whitespotted Grouper has been known to enter brackish and freshwaters areas for short times.  This fish can be kept in a brackish water tank that is at least 1.014 gravity.  These fish are ambush predators who hang out near coral or rock and wait for an unwary fish or crustacean to wander by!

Though this grouper is smaller than many groupers, reaching a little less than 12”, they still need a larger tank size than what most beginners have access to.  These fish, due to the large amounts of food they consume, need proper filtration for their large “output” of waste.  An oversized skimmer and two canister filters like Eheim or Fluval are a great way to help with water quality.  Clean these canister filters twice as often or more than the directions suggest to help them work effectively.  Tank mates that cannot be swallowed whole are fine.   A slender fish like wrasses, and even eels that are the same length as your Whitespotted Grouper will be consumed, since this “spaghetti” coils up in it’s belly.        

The Whitespotted Grouper can be kept with other hinds and groupers, but only one Whitespotted Grouper per tank.  They will eat any fish or crustaceans they can get in their mouths.  At times they will try to eat a fish they can’t quite get down their throat, and the aquarist will have to lend a hand to extract the unfortunate tank mate.  Other tank mates are safest if they are deep bodied and of similar size or larger.  Large angelfish, soapfish, larger triggerfish, large butterflyfish, larger tangs, pufferfish, adult Lionfish or other similarly sized and similarly aggressive tank mates are okay.  If attempting to keep with cleaner shrimp from the Lysmata or Stenopus genus, add them first.  Groupers may still possibly eat these shrimp if they are not well fed.  Whitespotted Groupers need to be the last fish added to an aggressive community tank.  

The aquarium should be at least 75 gallons, though 90 to 150 gallons is probably more reasonable.  The configuration of the tank can be shallow or deep.  Provide at least two areas in which the Whitespotted Grouper can hide out.  Provide more hideouts if there are other groupers, since each will defend their hiding places.  Well arranged live rock work will help them to adjust and will help provide the biological filtration (along with a strong skimmer and canister filters) that are needed for these large fish.  Water movement and light are not as important as offering them a varied diet of crustacean flesh when young, and larger diets of saltwater sourced fish flesh when they are adults.  Feed them several times a day as very small juveniles, then once a day as adolescents, and only 2 to 3 times a week to satiety as adults.  They prefer to hide under ledges and in caves, but will sit at the bottom of the tank near their hideout as they become more comfortable.  

White-spotted Grouper – Quick Aquarium Care

Aquarist Experience Level:Beginner
Aquarium Hardiness: Very Hardy
Minimum Tank Size:75 gal (284 L)
Size of fish – inches: 11.8 inches (29.97 cm)
Temperament:Large Aggressive – Predatory
Temperature: 72.0 to 81.0° F (22.2 to 27.2&deg C)
Range ph:8.0-8.3
Diet Type:Carnivore
whitespotted grouper
Image Credit: Jesus Cobaleda, Shutterstock

Habitat: Distribution / Background

The Whitespotted Grouper was originally found in the Indo-West Pacific from East Africa to the Ryukyu Island, Fiji, Marshall Islands, New Caledonia and the northern part of Australia including the Great Barrier Reef.  Some report sightings in Tonga.  These groupers prefer lagoon reefs and shallow coastal reefs in the small spaces between coral like LPS, namely Hammer Corals (Euphillia ancora) and Branching Hammer Corals (E. parancora), although they can be found in small spaces between SPS corals and reef rock as well.  They prefer depths from 16 to 82 feet (5 to 25 m), with adults usually at 66 feet (20 m) or deeper.  These ambush hunters sit and wait in their little hiding spot during the day, but actively hunt at dusk and at night, eating any fish or crustacean that fits into their mouth. Groupers often follow foraging eels in hopes to get an easy dinner, as the eel flushes fish out of narrow hiding places within the reef.   

As adults, Whitespotted Groupers are found alone but get together to spawn.  They will defend their home cave or area from any intruders.  They will first perform lateral displays and open their huge mouths to intimidate their opponent.  Next, they will start to chase and nip until the other fish is driven out of their territory.  If a rival grouper wants to fight, both fish will face each other and lock jaws for up to 5 minutes!  The loser, typically the weaker fish, will then swim off.

The Whitespotted Grouper is listed as Least Concerned on the IUCN Red List for Endangered Species, with an unknown population trend.

Similar Species:

  • Summan Grouper (Epinephelus summnana) – This fish is only found in the Red Sea and grows to double the size of the Whitespotted Grouper.  The Summan Grouper does not have the white short lines as adults on the body, and has smaller pectoral fins and shorter pelvic fins.
  • Scientific Name: Epinephelus sp.
  • Social Grouping: Solitary – Only one Whitespotted Grouper per tank.
  • IUCN Red List: LC – Least Concern – Only one Whitespotted Grouper per tank.

Description

The Whitespotted Grouper has various color phases from their juvenile stage to full grown adult.  Small juveniles less than 2.4” (6 cm) are brown all over with a dense number of white spots, yellow to orange pectoral fins and several oval white spots on the front part of their dorsal fin.  By 3.9” (10 cm) the white spots on their body start to elongate, forming a pattern of dashes or ovals over the body.  Adults have white spots that form irregular rows with white blotches that are as big or bigger than their eyes, and have a black steak along the top of the upper jaw.  Their pelvic and pectoral fins are longish and they have dark margins on the back of their dorsal, tail and anal fins.  Whitespotted Groupers have eyes that are mounted near the top of the head, which is typical for predatorial fish.  They can reach 11.8” (30 cm) and groupers are known to live from 9 to 37 in the wild, possibly longer in captivity with proper care. 

  • Size of fish – inches: 11.8 inches (29.97 cm) – 11.8” (30 cm)
  • Lifespan: 37 years – Groupers are know to live 9 to 37 years in the wild.

Fish Keeping Difficulty

Whitespotted Groupers are easy to care for as long as their needs are met.  Provide them with a tank that is at least 75 to 90 gallons and several hiding places within the live rock.  Some websites suggest the tank needs to be 150 gallons, and this is not out of the question, especially if you are considering more than one grouper, since these large fish produce a lot of waste and higher water volume will help keep up the water quality.  A 12” grouper is a much bigger fish and needs more water volume than a 12” wrasse.   Once full grown, they will require at least 2 hiding places, which they will defend aggressively.  The tank should have a heavy duty skimmer and a few canister filters due to the large amount of waste this fish produces.  Although some individuals may need live foods to elicit a feeding response, aquarists can easily switch them over to prepared foods.  Feeding groupers freshwater fish will cause health issues if continued for too long.  Do not house them with other Whitespotted Groupers, although they will be fine with other groupers as long as the tank is large enough and they have a different pattern on their bodies.

  • Aquarium Hardiness: Very Hardy
  • Aquarist Experience Level: Beginner – Aquarist needs a tank that is 75 to 150 gallons.

Foods and Feeding

The Whitespotted Grouper is a carnivore.  They can be fed any prepared foods for carnivorous fish, including frozen krill, scallops, fish and shrimp flesh from saltwater sources, and live small saltwater fish.  Live or frozen freshwater fish should only be offered sparingly, since there is not much in the way of nutrition in them, and can cause fatty liver disease in your grouper.  Feed very small juveniles several times a day, average sized juveniles twice a day, adolescents once a day and eventually feed adults 2 to 3 times a week until full.  Higher temperatures will make for a hungrier groupe

  • Diet Type: Carnivore
  • Flake Food: Occasionally – Juveniles will sometimes eat flake food for carnivores.
  • Tablet / Pellet: Occasionally – Sinking pellets for carnivores.
  • Live foods (fishes, shrimps, worms): Some of Diet – Live shrimp or feeder fish to get a reluctant new grouper to start feeding.
  • Meaty Food: All of Diet – Offer a varied diet of different saltwater crustacean and fish flesh.
  • Feeding Frequency: Daily – Juveniles several times a day, adolescents once a day and adults 2 to 3 times a week until full.

Aquarium Care

Groupers are hardy and fairly easy to keep, although they do need good filtration.  Live rock and a strong skimmer are a start.  Two good canister filters like Eheim that can be cleaned regularly, not every 3 or 4 months but bi-weekly to monthly to stay effective. They do well when provided good water conditions and a well maintained tank. Guidelines for water changes with different types and sizes of aquariums are:

Fish only tanks:

  • Medium sized up to 90 gallons, perform 20% to 30% monthly depending on bioload. 
  • Large Tanks 100 gallons and over, once water is aged and stable can be changed 20% to 30% every 6 weeks depending on bioload.

Reef tanks:

  • Medium sized up to 90 gallons, perform 15% bi-weekly. 
  • Large Tanks 100 gallons and over, once water is aged and stable can be changed 10% bi-weekly to 20% monthly, depending on bioload.

For more information on maintaining a saltwater aquarium see: Saltwater Aquarium Basics: Maintenance. A reef tank will require specialized filtration and lighting equipment. Learn more about reef keeping see: Mini Reef Aquarium Basics.

  • Water Changes: Bi-weekly – Standard maintenance is bi-weekly water changes of 15% every 2 weeks or 30% a month. If there are corals in the tank then 5% weekly to 15% every 2 weeks, depending on the tank size.
  • Water Changes: Bi-weekly

Aquarium Setup

In a minimum 75 gallon tank (283 liters), arrange live rock, forming several places for the Whitespotted Grouper to hide, especially if the fish is a juvenile.  As the fish grows, resize their hiding places, and as an adult, provide at least two places for them to hide.  If housing more than one grouper, tank should be over twice as big.  Each grouper in the tank will need 2 places to hide and live rock arranged to block their vision from each other to help tone down aggression.  The Whitespotted Grouper is not picky about substrate or lighting.  Keep the water at a stable temperature, which can be 72˚F to 81˚F (22˚ to 27˚C).   They can be kept in a brackish water tank, but this should be kept at the minimum of 1.014 salinity.  They can be kept from 1.014 to normal seawater salinity of 1.023, with a pH of at least 8.0 to 8.4.  Whitespotted Groupers prefer the bottom of the tank near their hideout.

  • Minimum Tank Size: 75 gal (284 L) – 75 gallons (283 liters) – Some websites suggest 150 gallon tanks.
  • Suitable for Nano Tank: No
  • Live Rock Requirement: Typical Plus Hiding Places
  • Substrate Type: Any
  • Lighting Needs: Any
  • Temperature: 72.0 to 81.0° F (22.2 to 27.2&deg C) – 72˚ F (22˚ C) 81˚ F (27˚ C)
  • Specific gravity: 1.014-1.025 SG
  • Range ph: 8.0-8.3
  • Brackish: Yes – With minimum of 1.014 salinity with a minimum of 8.0 pH
  • Water Movement: Any
  • Water Region: Bottom

Social Behaviors

Whitespotted Groupers are found alone in the wild, and this is probably the best way to keep them in captivity.  If keeping with a grouper that is a different species or genus, they should have a different color and pattern than they have.  Them as juveniles at the same time and add them last to an aggressive community tank that is at least 200 gallons or more since they are very territorial.  Also, arrange the live rock to provide barriers where their vision of each other is blocked from their normal hangout.

Tank mates that will not fit in their mouths are ideal.  Which that in mind, long thin fish or even eels that are the same 12” length as the Whitespotted Grouper will be easily consumed, since the prey fish coils up in the stomach of the grouper!   Even some wrasses are usually consumed due to their more narrow bodies.  If they are not as deep bodied, such as tangs and triggerfish, these fish should be at least 9” long.   Deep bodied fish that are at least 7” long and grown large lionfish, soapfish, large angelfish, and large butterflyfish are usually ignored.  The only time the Whitespotted Grouper becomes a threat, is if it is full grown and these other fish are not, and they fit into their mouth!  Keeping your grouper well fed will prevent this desperate action.  Add the Whitespotted Grouper as the last fish into an aggressive reef or fish only tank.

Whitespotted Groupers will not bother corals.  Due to their size, they may knock a coral over, so secure any corals firmly to the rock.  If the coral needs very clean water, you may not want to buy it, since these large fish foul up the water rather quickly.  Figure out what kind of water quality you can maintain and only buy corals that are not picky.

Starfish are safe, but snails, shrimp, and crabs will be eaten.  If you want to keep the cleaner shrimp that are often found cleaning the grouper, such as the Lysmata species or the Stenopus species, add the shrimp first and make sure the fish is well fed.  A hungry Whitespotted Grouper may eat the shrimp! 

  • Venomous: No
  • Temperament: Large Aggressive – Predatory
  • Compatible with:
    • Same species – conspecifics: No
    • Peaceful fish (gobies, dartfish, assessors, fairy wrasses): Threat
    • Semi-Aggressive (anthias, clownfish, dwarf angels): Threat
    • Monitor – Some larger 6” adult Damselfish should be safe.
    • Large Semi-Aggressive (tangs, large angels, large wrasses): Safe – Tangs and triggerfish at least 9” and larger wrasses that are at least 12.”
    • Large Aggressive, Predatory (lionfish, groupers, soapfish): Safe – Small 12” eels will be consumed

    • Threat
    • Anemones: Monitor – Water quality must be kept up to keep these creatures healthy.
    • Mushroom Anemones – Corallimorphs: Monitor – Water quality must be kept up to keep these creatures healthy.
    • LPS corals: Monitor – Water quality must be kept up to keep these creatures healthy.
    • SPS corals: Threat – Water quality must be excellent for these corals.
    • Gorgonians, Sea Fans: Monitor – Water quality must be kept up to keep these creatures healthy.
    • Leather Corals: Monitor – Water quality should be monitored.
    • Soft Corals (xenias, tree corals): Monitor – Water quality should be monitored.
    • Star Polyps, Organ Pipe Coral: Monitor – Water quality should be monitored.
    • Zoanthids – Button Polyps, Sea Mats: Monitor – Water quality should be monitored.
    • Sponges, Tunicates: Monitor – Water quality should be monitored.
    • Shrimps, Crabs, Snails: Threat
    • Starfish: Safe
    • Feather Dusters, Bristle Worms, Flatworms: Safe
    • Clams, Scallops, Oysters: Monitor – Water quality must be kept up to keep these creatures healthy.
    • Copepods, Amphipods, Mini Brittle Stars: Safe

Sexual differences

Males are larger than females.

Breeding / Reproduction

The Whitespotted Groupers are found alone in the wild, but come together in large spawning aggregations.  In the Okinawan region, there were studies of the spawning times of these fish.  The Whitespotted Grouper is a protogynous hermaphrodite, which means all of them are born female and become males at certain ages or sizes.  Unlike many other fish that are oriented this way, the grouper cannot just change into a male when the resident male disappears.  One of the areas where the Whitespotted Grouper spawns has a lot of SPS corals from the bottlebrush and branching Acropora groups.  They were tracked as migrating to the spawning area and spawned during the last-quarter moons of the April and May.  These groups or aggregations can number from 200 to 100,000 fish.  All the males and females release their gametes at once into the water column simultaneously.   

Whitespotted Groupers have not been bred in captivity.

  • Ease of Breeding: Unknown

Fish Diseases

Typically groupers are extremely hardy, but do tend to come in with multiple parasites.  A culture was done on wild-caught groupers and there were 11 to 16 different species of parasites found on their bodies, including nematodes and cryptocaryon.  Quarantining a grouper is absolutely necessary.  Happily, the grouper will respond to treatments for any parasites they are carrying.   

The most easily cured parasite is Crypt (salt water Ich), but they are all treatable if caught in a timely manner. Marine Velvet is a parasitic skin flagellate and one of the most common maladies experienced in the marine aquarium.  It is a fast moving that primarily it infects the gills.  Then there is Brooklynella, which kills within 30 hours, however, an even nastier killer is Uronema, which will kill fish overnight!   Uronema is often contracted when the aquarist doesn’t lower their salinity to the proper level of 1.009.  The Uronema parasite thrives in mid-level brackish water salinity, which is a specific gravity of around 1.013 to 1.020.  Treat for any illness at a normal salinity with a specific gravity of about 1.023 if the fish cannot handle low salinity, otherwise, lower the salinity to exactly 1.009, no less, no more.  Quick Cure and other 37% Formalin products will work perfectly well in both salinity ranges, but the lower 1.009 will help with the oxygen level. The amount of oxygen in the water increase as the salinity level is reduced.   

Anything you add to your tank from another system that has not been properly cleaned or quarantined, including live rock, corals, equipment and fish can introduce diseases.  A few other ways to proactively prevent disease are to provide quality foods, clean good quality water, and proper tank mates.

Availability

Whitespotted Groupers are found online and are reasonably priced.

Sources

 

 Whitespotted grouper (Epinephelus coeruleopunctatus) (Image Credit: Rickard Zerpe, Wikimedia Commons CC BY-SA 2.0 Generic)