Incidental Breeding of Roach (Rutilus rutilus) in an Aquarium

Spawning of roach (Rutilus rutilus) in a glass aquarium was accomplished after an 8-d exposure to a photoperiod of 16 h light: 8 h darkness. The aquarium received at least 3 h direct sunlight each day, which maintained the water temperature at 18-20°C during the day. This suggests that the temperature stimulus was strong enough to induce spawning in roach even in the artificial aquarium environment.