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Masked Julie – Julidochromis transcriptus

Masked Julie - Julidochromis transcriptus

Cichlids are a very ancient and extensive classification of fishes dating back millions of years before, for example, dinosaurs. Cichlids probably originated around 550 million years ago (give or take a month or two 😀) and there are somewhere in the region of 2,000 to 3,000 different species, of which around 1,700 have been classified (at the time of writing).

Cichlids can make excellent community fish but you should take care because not all Cichlids are good community fish and may devastate an established aquarium, treating their tankmates as food, so before choosing a Cichlid, please ensure that you know whether or not your choice will be appropriate to your needs.

Is Masked Julie (Julidochromis transcriptus) a good community fish? Masked Julie (Julidochromis transcriptus) should be considered to be an excellent community fish assuming that the community is one of non-aggressive, hard water, non-predatory species. Masked Julie (Julidochromis transcriptus) is suitable for all community aquariums although it can be somewhat gently territorial during breeding. 

Key Facts about Masked Julie (Julidochromis transcriptus)

CategoryKey Facts
Common name(s)Masked Julie Cichlid
Scientific nameJulidochromis transcriptus
Originate fromNorthwestern shore of Lake Tanganyika in Africa
Care requiredEasy to care for and very unusual
TemperamentRelatively placid cave/crevice-dwelling species
Colour & Formelongated, marbled body with very slender finnage
LifespanUp to 8 years
Adult size3 inches – Male smaller than female
DietOmnivorous – eats Daphnia, Bloodworm, Tubifex worms and pellet or flake food in the aquarium.
Aquarium size36 inches in length or greater
Compatible withSpecies that can also tolerate acidic water
Avoid keeping withLarge and/or aggressive species in too small an aquarium
BreedingEasy if you put the fish in the right environment.
Water temp73 – 82 Fahrenheit
Water pH7.6 to 9.0
Water hardness (dGH or dH)15 to 25 dGH

Origins of Masked Julie (Julidochromis transcriptus)

Masked Julie (Julidochromis transcriptus) is found only along the northwestern shore of Lake Tanganyika in Africa. At the time of writing, Masked Julie (Julidochromis transcriptus) there are only around eight known species of the genus, Julidochromis.

It is usually found in nature in shallow, rocky habitats that are rich in sediment and typically will be observed amongst the cracks and fissures of that environment

Basic Characteristics of Masked Julie (Julidochromis transcriptus)

Masked Julie (Julidochromis transcriptus) will grow up to around 3 inches in length and the female will tend to be the larger of the adults. In young fish, it is difficult (pretty impossible) to distinguish between the sexes so if you are purchasing young fish then buy half-a-dozen or more and you should have a mix of the sexes. With Masked Julie (Julidochromis transcriptus) it is generally advised to purchase half-a-dozen fish and when you find that two of the group have paired off then the remaining fish should be moved to a different tank.

Masked Julie - Julidochromis transcriptus
Masked Julie (Julidochromis transcriptus)

There is very little if anything to distinguish the male from the female and because the species is a cave-breeder you will be lucky, even then, to be able to sex the pair accurately. 

In shape, Masked Julie (Julidochromis transcriptus)  resembles a Wrasse, with its relatively long (compared with its depth) and slender body, long, but low dorsal fin, long, slender anal fin and relatively short tail.

The Masked Julie (Julidochromis transcriptus) has evolved to make best use of its environment and get to places where potential predators have no chance of reaching.

The lifespan of Masked Julie (Julidochromis transcriptus) is around five to eight years but this can vary enormously depending on tank conditions and general health.

Masked Julie (Julidochromis transcriptus) prefers hard, alkaline water, with a pH of 7.6 to 9.0 in and a temperature range between 73 and 82 degrees Fahrenheit and from 15 to 25 dGH.

Masked Julie (Julidochromis transcriptus) enjoys hard, alkaline water conditions so it will be comfortable with other species of similar size that prefer this type of water chemistry.

Masked Julie (Julidochromis transcriptus), being Cichlids, will defend themselves so it will be best not to keep them with aggressive species. Also, being relatively small and very slender a larger fish, given the chance, might try to it as a snack, if only it could get so close.

The Masked Julie (Julidochromis transcriptus) gets on well with pretty well all other fishes (that are not reputed to be predatory) and, because it has a small mouth, it is unlikely to eat small species.

Masked Julie (Julidochromis transcriptus) will generally dwell near the bottom of the water column and will enjoy a fine substrate, and plenty of rocks with crevices and caves.

The physical appearance of Masked Julie (Julidochromis transcriptus)

Masked Julie (Julidochromis transcriptus) has a slim body in height and width compares with its length. It is a slim species in the way that a Barracuda or Pike is slim. The body is grey in color with black, marbled areas all over, including the fins but excluding the clear (hyaline) pectoral fins. 

The marbling along the head tends to run horizontally, whereas, behind the gill plates, the marbling tends to be oriented vertically.

A few more characteristics may be described as follows:

  • The dorsal fin is shallow, with plack rays and a pointed tip at the top rear.
  • The caudal fin is mottled with the black marbling, is short and has a black outline at the tip.
  • The ventral fins are swept back and have a black leading edge running right to the tip.
  • The anal fin has a black leading edge, black rays along the front half but black marbling at the rear half and the rear half of the fin is marbled like the caudal fin.
  • The lips are quite thick and are more black than grey and the upper lip is the more prominent.
  • The eyes ave a beautiful, turquoise, horizontal band running front to pack and over the top of the iris.

The female, adult Masked Julie (Julidochromis transcriptus) tends to become the larger of the pair but this can be marginal to imperceptible and is unreliable for sexing the species.

The living environment for Masked Julie (Julidochromis transcriptus)

Masked Julie (Julidochromis transcriptus) enjoys being in and around rocks and crevices, resting and breeding in caves and only one adult pair from a single generation should be kept in the aquarium.

Masked Julie (Julidochromis transcriptus) will appreciate a soft substrate, as they will tend to wriggle to make new crevices under the rocks in the aquarium.

Note that Masked Julie (Julidochromis transcriptus) will generally mate for life and, being biparental, they will make good parents for any brood that they are rearing. Indeed, fry from the parent’s first brood will help to raise and protect fry from the next generation. This is unusual behavior and remarkable because of it.

It is recommended that Masked Julie (Julidochromis transcriptus) are kept as a small shoal only until two of the adults have paired up, after which, the remainder of the shoal should be relocated to a different aquarium. The male, in particular, can be gently territorial but setting up the tank so that sightlines are broken up will mitigate the risks of territorial behavior in general. 

When purchasing Masked Julie (Julidochromis transcriptus) it is generally recommended to buy around six fish. It will be impossible to sex the fish when purchasing them as immature specimens but, in due course, they will find their own mate and are, from that point, generally both monogamous and biparental.

Overall, Masked Julie (Julidochromis transcriptus) are the most attractive, unusual and elegant addition to your aquarium.

The diet of Masked Julie (Julidochromis transcriptus)

Masked Julie (Julidochromis transcriptus) is primarily omnivorous but has a preference for live food, feeding on a range of invertebrates in nature. In the aquarium a diet of live or frozen Artemia, Bloodworm and Daphnia is recommended and Masked Julie (Julidochromis transcriptus)  will readily eat pelleted food and flake food. That said, they prefer to stay close to the bottom of the water column and sift through the substrate for their food. For this reason, a fine substrate is recommended.

Sexual differences in Masked Julie (Julidochromis transcriptus)

It is very difficult to distinguish the sex of the adult Masked Julie (Julidochromis transcriptus). The adult female is significantly larger, especially at breeding times but this is unreliable. The female is also fuller-bodied when viewed from above when carrying eggs (gravid) but, again, this is unreliable because the female lays only 30 to 50 eggs. 

Aquarium size for Masked Julie (Julidochromis transcriptus) 

It is generally advised that the minimum tank size for Masked Julie (Julidochromis transcriptus) should be one of at least 36 inches in length or more due to the fact that a shoal of around six per species should be maintained initially and the adult fish are territorial withing their own species and within their own genus. This will enable your Masked Julie (Julidochromis transcriptus) to find an area of the aquarium which the pair can call home. A smaller tank will be too restrictive (unless it is a breeding tank) and the fish will suffer as a result whilst a larger tank is always to be recommended.

In a community tank, including some floating Java Moss will give smaller fish and any fry a safe haven from larger or more vigorous species and it certainly helps to break up the sightlines in the aquarium. Plenty of rocks are advised for Masked Julie (Julidochromis transcriptus)  because they will tend to stick close to their own outcrop and keep other fish away.

There is a predominance of so-called “Nano tanks” available but, being old-fashioned, I prefer my fishes to live in an environment which, at least, attempts to mimic nature, rather than living in what I would liken to a piscine prison cell. The tank should be well-planted but with clear areas where the fish can swim freely. The water should have a certain amount of movement, as Masked Julie (Julidochromis transcriptus) enjoy a flow of water.

Masked Julie (Julidochromis transcriptus) – Videos

Caring for Masked Julie (Julidochromis transcriptus) – video

Breeding Masked Julie (Julidochromis transcriptus) – video

Are you keeping tropical fish as a hobbyist or as a breeder?

This is a question too often ignored in my humble opinion. If you are a breeder (either commercially or as a hobbyist who gives away young fish to other hobbyists) then you will need the resources to move fish into breeding tanks in order to maximize the yield of fry that will grow up either for sale or to give them away.

If you are keeping fish for the joy of observing them in something resembling a natural habitat then you may feel that it is appropriate to allow nature to take its course and, as and when different species breed, then many of the eggs (and surviving fry) will be eaten either by their parents or by other fish in your aquarium. This is the natural order of things because this is what will happen in nature. The fittest may well survive to reach adulthood.

Ultimately, the choice is yours to make.

How do Masked Julie (Julidochromis transcriptus) breed?

In total, the female Masked Julie (Julidochromis transcriptus) could lay between 30 to 50 eggs during a single spawning. Masked Julie (Julidochromis transcriptus) is a cave breeder so you are unlikely to see them breed.

Typically, the female will lay her eggs on the sides or top of the cave and the male will then fertilize them. You could try a plant pot laid on its side and half-buried in the substrate but you would be best advised to cover the front with a rock, allowing room for the male and female to come and go.

Masked Julie (Julidochromis transcriptus)  eggs will hatch in around two to three days and the fry will become free-swimming several days later. This is conditional on water temperature and condition.

At breeding time it is advised not to change anything in the tank because a sudden change can cause the pair to separate and one of them is likely to die, as the result.

It is generally true that Masked Julie (Julidochromis transcriptus) make really good parents and will not prey on their own young. In general, the male will protect the territory whilst the female will tend to care for the eggs and fry but these roles are interchangeable.

Masked Julie (Julidochromis transcriptus) will guard their brood for up to six months to ensure a good survival rate. As previously mentioned, Masked Julie (Julidochromis transcriptus)  fry may well help raise the next generation of their parents but it is generally advised to move young Masked Julie (Julidochromis transcriptus)  to a new tank once they get to around one inch in length.

The female will tend to stay close to the eggs, fanning water over them which will remove and unfertilized eggs and thus protect the rest from the risk of fungus.

The male will provide “overwatch” around the broader area, gently warding off potential predators.

The Masked Julie (Julidochromis transcriptus) takes responsibility for post-spawning care and may become aggressive if it feels that the brood is threatened. For this reason, if possible, a breeding tank is recommended.

If Masked Julie (Julidochromis transcriptus) feels threatened, it will find shelter in plants or under rocks but it will defend its brood.

In a well-planted aquarium with floating Java Moss, the Cichlid will often spawn in the community tank and at least some of the fittest fry will survive to adulthood by hiding in the Java Moss or, with Masked Julie (Julidochromis transcriptus), in the crevices and caves of the rocks.

In a breeding tank, it is always a good idea to include a few aquatic shrimp, as they will consume any unfertilized or dead eggs but won’t tend to predate on viable eggs.

Breeding tank for Masked Julie (Julidochromis transcriptus)

You should prepare a tank of around twenty gallons in size with mature, hard, acidic and flowing water. The water should have a low level of light and broad-leaved plants together with lots of clusters of rocks which include crevices and caves in which the female will lay her adhesive eggs. 

It is recommended that the substrate consists of a fine substrate (sand) without sharp edges. 

Arrange your tank heating so that you can slowly remove up to half of the tank water and then replace it with collected rainwater (very slightly cooler than the aquarium water – but not so much that White Spot could result) and repeat this daily until the Cichlids spawn. This water and temperature change may encourage spawning, as it mimics nature. The rainwater is most important though some argue that tap water is fine.

Cichlids prefer to spawn where the water is flowing so a decent pump is required to synthesize that flow.

Feed up your Cichlids on bloodworm, which will sink to the bottom and burrow into the substrate. Your Cichlid will love rooting out the bloodworm and it can help to trigger spawning.

You may also wish to introduce baby brine shrimp, mosquito larvae or tubifex worms as an inducement to reproduction and live food will be very much appreciated. This will also tend to divert the attention of the Masked Julie (Julidochromis transcriptus) from preying on their own eggs and fry though cannibalism is not characteristic of Masked Julie (Julidochromis transcriptus).

Reduce the water movement by turning down the pump once the eggs are laid – only regular aeration is now required. Keep the lights off (or very low) and the tank dark (of fairly dark)  because eggs and fry can be particularly sensitive to the light.

The eggs will hatch typically in two to three days depending on tank temperature and conditions and the fry will become free-swimming after several days more. 

Keep the tank more-or-less unlit for the first week or so then gradually increase the lighting. Bear in mind that the eggs and fry of a fish as small as the Cichlid will be tiny indeed so you may need to use a magnifier “app” on your smartphone or a macro lens to see anything at all. A collection of eggs is generally easy to spot, as they look like a collection of tiny pearls.

The newly hatched fry will feed firstly on their yolk sac and remain static but, once free-swimming, can be fed infusoria and will also thrive on egg yolk during the first two to four weeks. 

Once the fry are free-swimming and their yolk sacs are depleted, then add baby brine shrimp and/or white worms. Once the fry are sufficient in size not to be treated as a snack then they can be introduced into the community tank where they will join the existing shoal. Before moving the adolescent fish into the community tank ensure that you have balanced the water temperatures to mitigate the risk of White Spot or other diseases being triggered.

Unless you are breeding commercially, you may wish to consider moving the fry into the community tank sooner rather than later. It may seem harsh but the adult fish in the tank will deal with any fry that are unlikely to survive to adulthood in the wild and you are synthesizing, to the best of your ability, a wild environment. The fittest fry will probably survive whilst the rest will be dealt with by the community.

Should your Masked Julie (Julidochromis transcriptus) have a special diet for breeding?

Adult Cichlids don’t need any particular inducement to breed. That said, it has been suggested that adding tubifex, bloodworm, or mosquito larva may encourage them, presumably because the addition of a new food may “fool” the fish into thinking that it is breeding time. From my own experience, I would always recommend keeping all of your fish in the best possible condition at all times, as this is good for the wellbeing of your fish.

Mike Wheeler

I started keeping freshwater tropical fish in 1972 and it has been something of a passion ever since. In this website, my aim is to build up an everyman's guide to help the everyday aquarist get the best from this inspiring and entertaining hobby.

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