 The fry spend a further 24 to 48 hours absorbing the yolk sac, whereupon they become free-swimming.At this stage, the fry should be fed with infusoria or a special egglayer fry food, and frequent partial water changes (around 10% of the aquarium volume every 24 to 48 hours) initiated.Having overcome the challenge of persuading the fishes to spawn, the aquarist soon discovers that the rummy-nose tetra presents another hurdle to successful captive reproduction—the fry are among the slowest growing of "all" characins, and indeed among the slowest-growing of all popular aquarium fishes.