Spawning report: Osteogaster schultzei (black cory)
Name: John Satterlee
Scientific Name of Fish* Osteogaster schultzei
Hobby Name of Fish: black cory
Method of Reproduction: Egg depositor
Number and Gender Distribution of Parents : Mixed group of 6 adults
Origin of Parents: Tank raised
Approximate number of eggs or fry* multiple batches of 20 ish eggs
Date of Hatch or Birth*
Date of Free Swimming If Hatched:
Approx. Number of Fry at 30 Days*
Jan/Feb hatch, photo Mar 2026, 7 fry
May/June hatch photo July 2026 3-4 more fry (among several other species in photo)
Aquarium Conditions:
pH 7.2
General Hardness: 150 ppm
Average Temperature (F) 72-82 depending on season
Salinity: None
Average Nitrate: less than 40 ppm.
Aquarium Size: 10 gallon
Water Source: Rockville town water
Water Changes: Every two months, 80-90% water change
Filtration System: Sponge filter
Additives: tablespoon of crushed coral
Décor:
Live Plants: Bolbitis
Hiding Places: Clay pot bottom askew on top of rock to provide cover
Substrate: Thin layer of pool sand
Lighting Type and Timing: Home depot shop light, 14 hours light, 10 hours dark
Food Fed to Parents and How Often* Tetramin flake food daily, Hikari algae wafers twice per week, Live baby brine shrimp twice a week. Live black worms as a treat every 2-3 weeks.
Breeding triggers: Water change and black worms.
Hatching eggs and feeding and raising fry: Eggs were observed on glass sides of tank. I collected these by hand and transferred them to a 5 in x 5 in sq plastic container filled about 1 in high with new dechlorinated water (not from parental tank). I added one alder cone and one half Indian almond leaf. Then I added an air stone and kept the container uncovered. After a few days the eggs hatched and the small fry could be seen darting around. My opinion is that the fry initially ate biofilm which grew on the leaf I added. I followed up by feeding the fry with small amounts of sera micron powder once or twice a day and baby brine shrimp every couple days. I did not do any water changes. After a few days I transferred the fry to a 5 gallon tank (with only 3 gallons of water) with a sponge filter, bolbitis, and a thin layer of sand. They were then fed as I feed the adults.
I found this cory species more difficult than most. I think the eggs are not as sturdy as other species and the hatch rate seems much lower than other species I have bred. I wonder if trying to hatch them in RODI water coulkd help?
