Z.4 – Corydoras Metae

Description

The pretty little bandit cory is a scaleless fish, so it requires good water quality. As a peaceful addition to a community tank, they get along very well with other small species. Very social, they do best in groups of three or more, but they are nocturnal feeders, so they may be shy during the day. During breeding season, however, this fish becomes extremely active, and their breeding rituals are carefully orchestrated.

Characteristics

Family	Callichthyidae
Origin	Colombia
Social	Peaceful
Tank Level	Bottom dweller
Minimum Tank Size	10 gallons
Diet	Omnivore, eats most foods
Breeding	Egglayer
Care	Easy to Intermediate
pH	6.5 to 7.0
Hardness	5 to 10 dGH
Temperature	72 to 79 F (22 to 26 C)

origin and Distribution

Corydoras metae was initially described in 1914 and subsequently named after Rio Meta, the river where it was first found. Rio Meta is an important tributary of the Orinoco River in Colombia and is the primary river of the eastern plains of Colombia. The bandit cory is endemic to the small rivers and creeks in this region. It is widely available in the aquarium trade and is among the most popular of the Corydoras genus.

Colors and Markings

The bandit cory is aptly named, due to the black band running from gill to gill, going over the top of the head and covering both eyes like a mask. The body is a pale beige with a pink tinge. All fins are colorless, except for the dorsal fin; the bottom two-thirds to one half of the dorsal fin is black, while the remainder is colorless. From the dorsal fin, a black stripe runs along the back ridge until it meets the caudal fin. This stripe then curves downward and runs parallel with the base of the tail, from top to bottom, ending without continuing into the tail itself.

As with other cories, the bandit cory possesses several specialized fin rays. These rays are reinforced, quite sharp, and can be locked into a rigid position to defend against a predator that might swallow this diminutive fish. The adipose, dorsal, and pectoral fins all have such spines. Keep these sharp spines in mind when attempting to net or handle cories, as they can cut both net and skin.

Bandit cories are among the armored catfish, which means they do not possess scales. Instead, their sides are covered by two rows of overlapping bony plates. Bony plates also cover their head. At the tip of the mouth are two pairs of soft barbels. These are highly sensitive to smell, allowing food to be easily located.

tankmates

Bandit cories are incredibly peaceful, making them well suited to community tanks with small to medium-sized, harmonious fish. Always keep them in schools of at least three of the same species, but preferably six or more. Never keep a single specimen, as it will become very timid. Solitary life for cories often leads to a much shortened lifespan.

Bandit Cory Habitat and Care

As with all cory species, the bandit cory forages through the gravel in search of food particles. A substrate with sharp edges can injure the soft barbels, which ultimately can lead to infection and even death. Always use sand or small smooth-edged gravel for corydoras habitat, preferably dark in color. Lighting should be subdued.

Arrange the tank with open areas for swimming. Driftwood or bogwood, as well as plants, make good hiding places for cories. Extended periods of lower or higher than normal water temperatures are not recommended for this species, so regular maintenance is essential. Corys are sensitive to poor water conditions; avoid all salt, copper, and most medications with all scale-less fish, such as the bandit cory. The use of such products is likely to cause more harm than the disease being treated.

Bandit Cory Diet and Feeding

Easy to please, the bandit cory will eat a wide variety of foods. Flake food and sinking pellets or tablets are the most common diet. Brine shrimp, daphnia, and bloodworms should also be included in their diet, either freeze-dried or frozen. Whenever possible supplement with live foods.

Remember that the bandit cory is a bottom-feeding fish, and will only eat food that sinks to the bottom or is delivered to that depth via tongs and lodged. They also tend to be nocturnal feeders, as that is when they are most active. Give them a meal just before turning out the lights for the day.

Gender Differences

Bandit cories are most easily sexed when viewed from above. The female will be much rounder and wider than the males. Males are also smaller overall than the female. The ventral fins of the mature male are more pointed than those of the female.

Breeding the Bandit Cory

Cories are seasonal spawners, responding to changes in the water chemistry and temperature that occur during the rainy winter season. Mimicking these seasonal changes is an excellent way to induce spawning. This can be done by reducing the temperature, making the water softer, and lowering the pH (do not lower below 6.0).
Perform a water change every other day with water that is several degrees cooler than the tank. Adding peat to the filter or using blackwater treatment will reduce the pH while softening the water. Test the water to ensure that pH is not too low.

The spawning group should consist of two males per female, if possible. Condition the breeders with a variety of live and frozen brine shrimp and worms. The females will get plumper as they fill with eggs, indicating that they are nearly ready to spawn. At this point, the breeders will become very active and lively. This activity may continue for several days before spawning takes place.

Activity in the tank will continue, going through periods of intense movement followed by rest periods. Females may remain stationary and disinterested at times. Males will dart about, or remain in place shaking their bodies. It is not unusual for males to engage in mock fighting. The instant the female moves, the males will become excited and spring to action, pursuing the female relentlessly.

When a female is receptive to spawning, she will allow the male to caress her barrels and ultimately take up a “T” position in front of her head. While in this position the female brings her pelvic fins together, creating a basket into which she releases one or two eggs. The male subsequently releases sperm that fertilizes these eggs.

Once fertilization occurs, the female swims away with the eggs and finds a suitable site to place them. Males will eagerly await the placement of the egg, sometimes chasing the female before she is done. This process will repeat itself until 60 to 80 eggs are laid (not all eggs are fertilized). Bandit cories typically have a 50 to 80 percent fertilization rate.

Adults will eat the eggs, so parents and eggs must be separated after spawning. Many breeders find it easier to move the eggs, rather than the adults. If the eggs are affixed to plants, the entire plant may be moved. When eggs are attached to the glass, they can be carefully rolled off using your fingertip.

The rearing tank should have water of the same temperature and chemistry as the breeding tank. Use a sponge filter, and add a few drops of methylene blue to the water to prevent egg fungus. Promptly remove any eggs that develop fungus. Cherry Shrimp are sometimes used in rearing tanks, as they eat diseased eggs, but will leave healthy eggs untouched.

Eggs will hatch in four to five days. After two to three days the fry will entirely consume their yolk sacs and should be fed freshly hatched brine shrimp. They may slowly be moved to larger foods as the fry grow. During this time, daily water changes are necessary. Any loss of large numbers of young fry will be generally due to failure to change the water and keep the tank clean.