About the Gosse Cory
Species Type: Freshwater Fish
Care Level: Easy. Does well in a slightly more narrow range of water parameters and shouldn't be used to cycle an aquarium. Will eat most prepared foods. May have some specific care requirements in terms of particular water parameters, social behaviors, food items etc.
Origin: Endemic to a few tributaries of the Rio Mamore in Rondonia state, Brazil.
Compatibility/Temperament: Very peaceful bottom fish, well suited for any community aquarium of non-aggressive fish. Must be kept in a small group, minimum three but preferably five or more.
This is one of the more distinctly coloured and patterned of the corys, and therefore is a nice contrast with the more common spotted varieties. It is identical in colour to Corydoras seussi but the latter's snout is long whereas C. gossei has a rounded head. Interestingly, both these species occur in the Rio Mamore system but they are not sympatric.
The aquarium should be well-planted with pieces of bogwood, a dark substrate (small gravel or sand, provided it is smooth-edged) with some open areas, and subdued lighting which can be partly achieved by floating plants; corys do not like bright lighting. Though this species will swim mid-water to browse wood and plant leaves, it spends much of its time foraging the substrate. As with all corys, mature females are rounder when viewed from above.
The Corydoras are quite sensitive to water parameters and quality, and highly intolerant of salt, chemicals and medications. Signs of stress usually begin with rapid respiration, then lethargy (often just "sitting" on plant leaves, wood or the substrate respirating heavily, sometimes near the surface) and sometimes rolling onto one side. At such signs, a partial water change of at least 50% with a good water conditioner should immediately be made, and appropriate steps taken to remove the cause. Any sudden fluctuation in water chemistry or temperature often induces shock, causing the fish to "faint" and fall over on its side. Corydoras introduced to new aquaria will settle in better if the tank is established; Cory's do not adjust well to a new aquarium with still-unstable water conditions and fluctuations.
The dorsal, pectoral and adipose fins are each preceded by a spine which is actually a hardened and modified ray; the pectoral fin spine can be "locked" into position by the fish; care must be taken when netting Cory's not to entangle these spines, which can also give the aquarist a nasty jab. They are believed to be a defense adaptation, to lodge the fish in the throat of a predator.
All species in the genus will periodically and fairly regularly swim quickly to the surface for a gulp of air. The fish swallows the air and blood vessels in the hind gut extract oxygen from the air; it is then expelled through the vent the next time the fish breaks the surface for another gulp of air. This adaptation is believed to have evolved so that the fish can survive in poorly-oxygenated water such as drying pools during the dry season. It is however essential to the fish's well-being that it regularly swallows air.
The genus name is derived from the Greek "cory" meaning helmet, and "doras" meaning skin, incorrectly used here for "armour"; it refers to the dual row of overlapping plates (instead of scales) along the body, comparable to a suit of armour. This species was described by H. Nijssen in 1972 and named in honour of Dr. Jean-Pierre Gosse who collected the first specimens.
Gosse Cory Diet
Feeds on worms, crustaceans and insect larvae in its habitat, but readily accepts prepared sinking foods like tablets and pellets with frozen bloodworms and live worms a treat.
Attains 2.4 inches.
Minimum Tank Suggestion
24 inches in length.
Ideal water parameters for Gosse Cory
Soft to moderately hard (hardness below 25 dGH, preferably below 12 dGH), acidic to slightly basic (pH below 7.0) water, temperature 22-26C/72-79F.