By: Carlos_X3

Corydoras information:
Scientific name: Corydoras
Common name: Cory catfish, Cory cats, Corys
Max size: 7 cm/ 3 inches
pH range: 6.0 - 8.0
dH range: 5 - 10
Temp. Range: 22 - 28 C /72 - 82 F

Corydoras, a type of catfish with over 150 species is a very popular low dwelling fish. Corys, as they are popularly called by their keepers, are peaceful and can be kept in tropical community aquariums. They are active and fun to watch, and can become very old in your aquarium if you provide them with good conditions. A healthy Cory will live 15-25 years

Corydoras classification:
The name Corydoras is derived from the Greek word kory (helmet) and doras (skin). Corydoras belong to the genus Corydoras which is part of the armoured catfish family Callichthyidae. Like other members of this family they will occasionally come to the surface for a gulp of air, this normal behaviour unless excessive. They have a sharp plates on their body which protects them from most aquarium predators that try to nip or attack them.

Corydoras in the aquarium trade:
Corys are popular varieties of aquarium catfish. They are hardy, active, very peaceful and highly recommended for beginners. Compared to the number of species of Corys, there are few kinds that are bred within the trade so most aquarium stock is wild caught simply because it has proven difficult to breed Corys. The most commonly bred are the Bronze Corys and from the Bronze come the Albino’s, Hi-fins and few others. Many Corys are bred in Florida.

Corydoras natural habitat and range:
Corydoras are found in small-sized streams, along the margins of large rivers, in marshes and ponds in South America. They are native to slow-moving and almost still streams and small rivers of South America where the water is shallow and very clear, soft and neutral or slightly acidic. Dense plants cover the sides and banks of these waters and this is where the Corys are found in the thousands, therefore should always be kept in groups of 6+. They are bottom dwellers and they constantly forage in their natural habitat feeding on insects and vegetable matter. Their feeding method is to search the bottom with their sensitive barbels and suck up food with their mouth, a soft substrate is preferable to avoid damage to their barbels.

Corydoras description:
Corys stay small but the females are longer, fatter and more fuller bodied. Different Corys display different body shapes and sizes. Some Corys show an iridescent pigmentation on parts of their bodies, sort of light green spots which shine in the light.

Corys tend to be more active at night, sometimes swimming up and down all over the tank once the lights go out. Corys are said to be nocturnal but this is false. Corys are in fact crepuscular meaning they are most active at twilight, dawn or dusk. Corys are naturally skittish, darting away as soon as they see you come close. An overly skittish Cory can be stressed out if freightend excessively, this can be treated simply by giving it more partners of the same specie or staying away from the front of the aquarium.

Corydoras behaviour and suitable tank mates:
Corydoras are a peaceful fish that are often kept in freshwater community aquariums with other non-aggressive fish species, although some have kept Corys with aggressive tank mates successfully it is not recommended. Corys are shy fish and it is recommended to keep them in groups of at least 6 as most species seem to form shoals or more commonly referred to as schools. Appropriate tank mates include small peaceful fish such as Tetras and Danios, larger fish such as Gouramis and Angels and other bottom dwellers such as African Frogs and Snails.

Corydoras setup:
It’s always best to mimic the natural Cory habitat, the Amazon River which is densely planted and filled with hiding spots. You can transform your aquarium into a natural habitat by adding lots of plants and caves of rock or wood. Corys are adaptable to water conditions and set up but that does not mean they will thrive and be happy in all conditions.

Corydoras care:
Barbels are needed to forage for food, if you notice your Corys barbels shortening it may be from a sharp substrate or a highly polluted substrate. Vacuum your substrate and go with gravel or sand for the bottom. Wild Corys inhabit very soft and slightly acidic waters in tropical regions of South America where the water temperature usually stays between 20 and 26° C (68 and 80° F), pH around 7.0. Rainforest rivers and streams are frequently replenished by soft downpour. Frequent water changes are therefore recommended in the aquarium, atleast 25% water changes each week. High nitrates and excessive exposure to high nitrates can prove unhealthy and lethal. Strive to keep your nitrates below 20, plants help keep nitrates down! It is extremely important to properly introduce your Corys to there new home, acclimate them properly and if you are not sure how to do this ask us in the forum section. Corys can adapt to conditions but poor or even moderate conditions will ultimately shorten there life span and growth.

Corydoras feeding:
Corys will search for food at the bottom of the aquarium, so sinking pellets are a must. occasional treats in the form of live or frozen meaty food and vegetable matter such as cucumber is greatly appreciated. Live foods include bloodworms, brine shrimp, insect larvae and others. As a staple diet I recommend Hikari sinking wafers, my Corys love them. Corys are often misfed and neglected by people who believe that Corys simply eat whatever matter is lying at the bottom, this is a huge misunderstanding. Corys will not eat what has rotted but they will feed on fresh fallen scraps of food.

This is the diet I supplement my Corys with; 2 or 3 servings a day of sinking wafers or shrimp pellets with occasional treats once or twice a week consisting of live frozen bloodworms and brine shrimp, they also enjoy tubifex worm cubes.

Corydoras disease:
Corys do not have common diseases but if neglected can develop or be susceptible to diseases. Diagnose and treat in a hospital or quarantine tank. Corys are sensitive to nitrites and nitrates, monitor your water parameters with a master test kit, treat your water with a conditioner and keep up on water changes. A lethargic or inactive Cory is a accurate sign of a sick Cory.

Comments and suggestions:
Corys are the most peaceful fish you will ever own you will never once see aggression from these interesting creatures. They are playful, fun and lively, a great addition to a peaceful community freshwater aquarium.


Sources: elmersaquarium.com, wikipedia.com, aquaticcommunity.com