In this work, the embryologic and larval development of fertilized street sweeper (Corydoras paleatus, Jenyns 1842) fish has been studied. The embryonic development of fertilized were completed at 48 hour at temperatures of 23 to 24 °C and 7 to 7.5 pH at a tropical fish breeding farm in Istanbul. At the end of the study, the hatching rate of 220 eggs were about 90 percent. The vitellus sac was absorbed after 36 hours later and the larvae were fed freely. During the free feeding regime at the first 10 days the larvae were fed with Artemia nauplii (3 to 4 times a day), and the following days (2 times a day) firstly Tubifex sp. and Artemia nauplii until 20th day. By the 20th day feeding is continued until 30th day by Tubifex. After 30th day, the larvae were fed with all kinds of dried or alive foods.
At breeding time by the sexual selection, the males were slim with long body and sharp dorsal fin. The females were swallen abdomen and large dorsal fin. As a result of the study, the environment conditions were influenced of growth and breeding of the fish. The rate of breeding is 90 percent, therefore the fish are an economic value at the aquarium market.