Green gold cory (Corydoras melanotaenia) care guide

Group
Freshwater fish
Other names
Green gold catfish, Osteogaster melanotaenia, Gold laser cory (loose trade name)
Family
Callichthyidae (armoured catfishes)
Origin
South America: the Meta River basin in Colombia (Orinoco drainage).
Water
freshwater
Maximum size
5.8 cm
Temperature
23–25°C
pH
6–8
Hardness
Soft to hard, 2–25 dH
Minimum tank
60 litres
Care level
beginner
Temperament
peaceful

Care

This cory has a greenish-gold body with a dark stripe along the back, which gives it the name green gold cory (FishBase lists it as the green gold catfish). The name "gold laser cory" is loosely used in the trade for several corys with a gold stripe, so check the scientific name before buying. Now classified as Osteogaster melanotaenia after the 2024 revision of the corydoradine catfishes; still sold as Corydoras melanotaenia. Keep a group of at least six in a tank of 60 litres or more (our estimate). Use fine sand so they can dig with their barbels, with plants, driftwood and some open sandy areas. FishBase gives 23–25 °C, pH 6.0–8.0 and hardness 2–25 dH. Keep the water clean and stable. Corys have no scales, only bony plates, and are sensitive to salt and to many medications (especially copper-based treatments), so use half doses or leave them out when treating a tank. Keep nitrate low with regular partial water changes and lightly siphon the sand so uneaten food does not rot. They gulp air at the surface now and then, which is normal. Take care when netting them: the fin spines are sharp and catch in nets. It reaches about 5.8 cm standard length. It is listed as Least Concern on the IUCN Red List (FishBase, assessed 2020), and FishBase notes it is commercially important in the aquarium trade. We could not read the PlanetCatfish page for this species when checking, so these figures come from FishBase and Wikipedia. Sources: FishBase (fishbase.se/summary/Corydoras-melanotaenia.html); Wikipedia (en.wikipedia.org/wiki/Corydorasmelanotaenia). Checked October 2026.

Diet

A bottom-foraging omnivore. Feed good-quality sinking pellets, tablets or granules, plus small frozen or live foods such as bloodworm, daphnia and brine shrimp. Make sure food reaches the bottom; corys should not be expected to live on leftovers.

Breeding

FishBase records that the eggs are stuck to broad plant leaves, that a spawning usually produces about 150–180 eggs, and that they hatch in about 5 days. As with other corys, condition the group well on live and frozen foods and use a large, slightly cooler water change to trigger spawning. Females are usually larger and broader than males. Move the eggs or the adults afterwards, as adults may eat them, and feed the fry on microworm and newly hatched brine shrimp.

Compatibility and tank mates

Peaceful and gregarious, and a good choice for a calm community tank with small tetras, rasboras, pencilfish, dwarf cichlids and other peaceful catfish. Avoid large or aggressive fish.

Last updated 5 October 2026. Community-edited care guide on Aquatic-Auctions.

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