The Oldwife may grit their teeth when frightened, but an aquarist without proper knowledge will be gritting their teeth about their purchase!  Yet with the proper research they are a great addition to a cold water marine tank!

The Oldwife looks a lot like a freshwater Angelfish, with that silvery to cream body and black or brown vertical stripes.  The stripes all extend from the top to the bottom of each area they are on.  There is a stripe through the eye, gills, from the top of the dorsal to the bottom of the pectoral fins, a thin mid body line, a thick bar from the tip of the second dorsal to the bottom of the anal fin, then 2 on the caudal fin area and one at the edges of the tail fin, and also the angled edges of the tail fin.  They have a yellow to red accent at the top of their eyes too.  They reach 19.5” (50 cm) and are mature at 11.4” (29 cm).   It it is unknown how long they live.

   They have venomous spines in their tall dorsal fins and if you do get stung, soak  the area in hot water that is 100 to 110˚F.  The name Oldwife comes from the sound that they make grinding their teeth when caught on a fisherman’s hook.  As if old wives are “chattering” about.  Coming from the southern half of the coasts of Australia, it gives us a hint as to their water temperature needs.  These temperate fish need to be in water that is 50 to 64.4˚F (10 to 18˚C) to live longer than a few months or a year.  This is one of those fish that you will regret buying on an impulse, unless you already have a 180 gallon cold water marine tank!

   These fish are best kept by advanced aquarists because they are moderately difficult to keep. While they are easy to feed and keep alive initially, it is long term that becomes a problem.  One challenge is the sheer size of the tank, another is the fact that is needs to be a cold water marine tank, which is not an easy accomplishment and last it can sometimes be difficult to get them to eat.  Their venomous spines can cause a serious wound.  When cleaning the tank, they should be partitioned off with something to keep them away from your arms and hands.

   Honestly, no one really knows their compatibility.  Some aquarists buy them and stick them in a warm tank with other peaceful fish and they get along, which is great until they expire from the heat.  There are very few fish that are known to be able to be kept with them in this cold water.  Subtropical fish endure a minimum of 65˚F, and may be kept with this fish, since this is the Oldwive’s highest temperature tolerance.  Tank mates should be peaceful and not fin nippers.  Although they are found in groups in the wild, like most marine fish, it may not be wise to keep more than one in a tank.  It is unknown if they are okay in a reef.

   Provide a tank that is at least 180 gallons and a chiller to keep the temperature between 50 and 64.4˚F.  Make sure there is great water movement, a strong skimmer and filtration.  These fish get very large and produce a lot of bio-matter.  Live rock with copepods from the cold water variety will help them to adjust to captive life.  Also, provide hermit or other crabs for them to eat.

Scientific Classification

Kingdom:Animalia
Phylum:Chordata
Class:Actinopterygii
Order:Perciformes
Family:Enoplosidae
Genus:Enoplosus
Species:armatus

Oldwife – Quick Aquarium Care

Aquarist Experience Level:Advanced
Aquarium Hardiness:Moderately Difficult
Minimum Tank Size:180 gal (681 L)
Size of fish – inches19.5 inches (49.53 cm)
Temperament:Peaceful
Temperature:50.0 to 64.4° F (10.0 to 18.0&deg C)
Range ph:8.1-8.4
Diet Type:Carnivore

 
 

Habitat: Distribution / Background

   Oldwife fish, Enoplosus armatus, was first described by White in 1790.  They only have a few common names which are Angelfish, Bastard Dory, Old Wife, Zebra Fish and Zebra-Tail. The name Angelfish is due to it’s similarly to the markings of a tropical or freshwater angelfish. While the name zebra is self explanatory when you look at the markings on the fish, and the term “Oldwife” comes from them grinding their teeth when captured with a hook and pole then held out of the water.   It is “annoying” to the fisherman, like the chattering of wives as the story goes.  I honestly cannot tell you why “Bastard Dory” is a common name!  These fish are the only ones in their genus and species!  The Greek word for their genus, Enoplos stands for “with weapons,” referring to their venomous dorsal spines.
    The Oldwife is found in colder marine and brackish water in the indo-Pacific around Australia, in the temperate waters just south of Queensland, and the coasts surrounding the southern 1/2 of Australia.  Adults are found on inshore and offshore over rocky bottomed reefs and in estuaries among seagrass beds.  Juveniles are found in estuaries.  The depth they are found at are up to 295 feet (90 m) in water that is temperate, from 50 and 64.4˚F (10.0 to 18.0° C).  They feed on zooplankton, planktonic crustaceans, zoobenthos and other benthic crustaceans.   These fish will either school in large numbers, in pairs or alone.  It is said they will set up cleaning stations in the ocean to clean other fish.

   The Oldwife is not on the IUCN Red List, as it has not been evaluated yet.

  • Scientific Name: Enoplosus armatus
  • Social Grouping: Varies – In the wild, the Oldwife can be found alone, in pairs or in large groups.
  • IUCN Red List: NE – Not Evaluated or not listed

Description

   The Oldwife is an elongated laterally compressed fish, that looks quite similar to a fresh water angelfish which is silver with black stripes!  The eyes have an accept color that can range from yellow to red. They have a compressed head and a small turned up mouth with a set of teeth that they grind and make a loud noise with when frightened and crush crustaceans. Their bodies are silver to cream with 6 to 8 vertical black or brown bars of various sizes, however there are 2 prominent and wider vertical bars.  One runs from the top of the first dorsal fin to the bottom of the pectoral and the second one runs from the top of the second dorsal fin through the bottom of the anal fin.  The others run over the eyes, gills, middle of the body and 2 on the caudal fin area.  The tail fin has black edging at the base and around the edges, except for the outer edge, forming a “C” shape if the fish is facing left.  The pale parts of the pectoral fins may have a pinkish hue.  They grow to 19.5” (50 cm) and mature at 11.4” (29 cm).  It it is unknown how long they live.
 

  • Size of fish – inches: 19.5 inches (49.53 cm) – They reach maturity around 11.4” (29 cm)
  • Lifespan: – unknown

Fish Keeping Difficulty

   Before purchasing, find out how long the store has had the fish.  If they have them in warm water for more than a few days then don’t purchase the fish.   These fish are moderately difficult to keep and are best kept by advanced aquarists.  This is due to their need for a very large tank of 180 gallons that is kept at 50 to 64.4˚F (10 – 18˚C).  Becuase this is rather cold,  you should have a chiller that can handle 180 gallons.  Housing them in warmer water would eventually prove fatal for them as their body’s metabolism would have to work overtime to sustain them even for a short time. They may need live foods like small hermit crabs to entice them to eat along with live foods growing on established live rock.  Provide a strong skimmer and good filtration and water movement for this big bio-load.  Another consideration is their venomous dorsal spines.  If you are unfortunate enough to get poked, soak the area in very hot water, that is 100 to 110˚F (37.78 to 34.3˚C).

  • Aquarium Hardiness: Moderately Difficult – Getting them to start eating can be difficult.
  • Aquarist Experience Level: Advanced – Ability to handle a large COLD marine aquarium is a must.

Foods and Feeding

   The Oldwife is a carnivore that feeds mainly on crustaceans.  They would do well to have a mature tank with live rock to provide cold water copepods and amphipods as well as smaller hermits.  Feed live foods until they start eating prepared foods.  Raw table shrimp, squid, mussels krill, brine or mysis can be offered.  They do not eat any veggie material.  Flakes are not nutritious enough and pellets may not be eaten, however if they do eat them then make sure they are for marine carnivores.  It is unknown how often they need to be fed, however when first acquiring them, offer food several times a day. 

  • Diet Type: Carnivore
  • Flake Food: No – Not nutritious enough
  • Tablet / Pellet: Yes
  • Live foods (fishes, shrimps, worms): Some of Diet – Natural foods on live rock and hermits and other small crabs make a reef aquarium advantageous.
  • Meaty Food: All of Diet
  • Feeding Frequency: Several feedings per day – Feed at least 3 times a day in small amounts to see if they will start eating, especially as juveniles.


Aquarium Care

  Oldwife fish, like most cold water fish, do not do well when water quality is neglected.

Fish Only Tanks:
-Large Tanks 100 gallons and over, once water is aged and stable can be changed 10% bi-weekly to 20% monthly, depending on bioload.

Reef Tanks
-Large Tanks 100 gallons and over, once water is aged and stable can be changed 20% to 30% every 6 weeks 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. Regular water changes done  bi-weekly will help replace the trace elements that the fish and corals use up.  

  • Water Changes: Bi-weekly

Aquarium Setup

   The tank size needed to keep your Oldwife happy and healthy would be 180 gallons and a chiller to keep the water cold.  If keeping with other Oldwife fish, the tank should be hundreds of gallons.  Provide live rock with several crevices for them to sleep in at night or retreat to if frightened.  Any substrate is fine and you may need to slowly adjust them to brighter light if you are doing a cold water reef.  A strong skimmer and moderate water movement is ideal to help keep the water quality in check.  They like temperatures between 50 and 64.4˚F, with an 8.1 to 8.4 pH reading.  

  • Minimum Tank Size: 180 gal (681 L)
  • Suitable for Nano Tank: No
  • Live Rock Requirement: Typical Amount
  • Substrate Type: Any
  • Lighting Needs: Any
  • Temperature: 50.0 to 64.4° F (10.0 to 18.0&deg C)
  • Breeding Temperature: – unknown
  • Specific gravity: 1.023-1.025 SG
  • Range ph: 8.1-8.4
  • Brackish: No – Unknown at what age they enter marine water. Best kept in full marine salinity.
  • Water Movement: Moderate
  • Water Region: All – Not exactly sure.

Social Behaviors

   Since there are few sources for information, the compatibility of the Oldwife is unknown.  They can be found alone, in  pairs or in large groups in the wild; however, caution is advised in keeping them in pairs or groups.  If we use a little forethought, we know that many marine fish are found in pairs or in large groups in the wild, yet in a captive environment they need housed as one per tank.  There really is no way of knowing  how to interpret the Oldwife’s compatibility with their own in captivity, so trying just one in the beginning may be best.

   It is unknown which other cold or subtropical fish they could be housed in captivity, but they should be peaceful.  Avoid fish that are prone to nipping at long fins like the Panther Puffer (which is also a cold water fish).  As for other fish that are okay in cooler water, peaceful fish the the Catalina Goby and the Blue Spotted Jawfish, which are subtropical, would work well.  Subtropical fish need a temperature range of 58˚F to 71˚F, and since temperate fish need 50 to 64.4˚F, the temperatures cross between 58 and 64.4˚F.  They will be compatible if the tank is kept between these temperature 58 and 64.4˚F.   One candidate, though doubtful, may be another subtropical Garibaldi Damsel (Hypsypops rubicundus).  Problem is, the Garibaldi Damsel is aggressive towards it’s own kind, so it may or may not bother the Oldwife.

   It is unknown if they would bother corals, yet due to the fact that their stomach contents are zoobenthos, zooplankton and crustaceans, they probably would be fine in a cold water reef set up.  They are not typically around a lot of coral so they may not even know what it is.  Maybe put in a frag of a cold water coral and see what happens.  Since there are not many corals where they are, they probably wouldn’t even know what it was.  For a short list of cooler water corals with photos see this article http://www.advancedaquarist.com/2009/5/short.

For the most part, any crustacean would be eaten.  As for the other inverts, it is unknown how they would react.  Shrimp and snails may be okay.

  • Venomous: Yes – Dorsal spines are venomous
  • Temperament: Peaceful
  • Compatible with:
    • Same species – conspecifics: Unknown – Best kept one per tank
    • Peaceful fish (gobies, dartfish, assessors, fairy wrasses): Safe – Catalina Goby and BlueSpotted Jawfish with water between 58 and 64.4˚F.
    • Semi-Aggressive (anthias, clownfish, dwarf angels): Monitor – Only the mellow versions of temperate and subtropical fish.
    • Monitor – Only the small versions of temperate and subtropical fish.
    • Large Semi-Aggressive (tangs, large angels, large wrasses): Monitor – Only the mellow versions of temperate and subtropical fish.
    • Large Aggressive, Predatory (lionfish, groupers, soapfish): Threat
    • Monitor – Only the mellow versions of temperate and subtropical fish.
    • Anemones: Monitor
    • Mushroom Anemones – Corallimorphs: Monitor
    • LPS corals: Monitor
    • SPS corals: Monitor
    • Gorgonians, Sea Fans: Monitor
    • Leather Corals: Monitor
    • Soft Corals (xenias, tree corals): Monitor
    • Star Polyps, Organ Pipe Coral: Monitor
    • Zoanthids – Button Polyps, Sea Mats: Monitor
    • Sponges, Tunicates: Monitor
    • Shrimps, Crabs, Snails: Monitor – Will eat crabs.
    • Starfish: Unknown
    • Feather Dusters, Bristle Worms, Flatworms: Unknown
    • Clams, Scallops, Oysters: Unknown
    • Copepods, Amphipods, Mini Brittle Stars: Monitor

Sexual differences

Unknown

Breeding / Reproduction

   Oldwife, or should that be Oldwives?  Anyhow, they spawn in June, July and August in waters near Victoria, Australia, and in September, October and November around the southern coasts of Australia.  The eggs are pelagic, smooth and round.  They hatch when they are 1/10th of an inch or 2.5 to 2.7 mm.  At that time, they start to develop a gill spine and have a heavily pigmented body and the color is darker on the upper and lower parts of the body and the tail fin.  By the time they are 8.7 mm or about 1/3 of an inch, they have developed all of their fins.  They swim down and settle in estuaries when they are .47 to .59 inches (12 – 15 mm) among seagrass beds and large algae crops on rocks.  

   There are no reports of this fish spawning in captivity.

  • Ease of Breeding: Unknown

Fish Diseases

Unknown

Availability

   Rarely found in the trade and can be quite pricey when they are available.


Featured Image Credit: Yakov Oskanov, Shutterstock