Chances are that cons breed every 2 weeks like clockwork. The female has to produce so many eggs, that she is in theory, stunting. The male quickly grows bigger and IF he decides to have a mean streak, he can kill her. Although not likely if paired young. The eggs take 3 days to hatch. After the 3 days, they hatch and go into thier wiggler form, consuming thier yolk sac. After 3-5 days they will become free swimming and can eat foods as big as finely crushed flakes, but will fare much better on baby brine shrimp, first bites, cyclops, daphina etc. When they gain some size, your instincts will tell you when to feed bigger foods. Eg, flakes.
Oh, and about breeding the rest of thier lives, think of it as a human being started to have kids at 13, and doesnt stop (Has kids every 9-10 months like clockwork) untill she reaches menopause. Thats what its like for female cons.