Just a quick update on this species, ccording to my observations.
Heroina isonycterina is a predator. For a few weeks my two fish had their way in my main home-tank (540 liters), which they shared with several tetras and other Cichlids like Ivanacara adoketa, Apistogramma gephyra and Biotodoma cupido. When the lights went out at night, I could hear the splashes as the Heroinas had their late night dinner. Gradually, the Tetras (Copella and Axelrodia) disappeared. The dominant Heroina ruled the tank, reducing the former rulers, the Ivanacaras, to pale spectators with his confident patrolling and extreme appetite. The other Heroina was chased out of sight as soon as it emerged from the dense plantation. Bearing in mind that my heroinas are still far from full grown, I can only imagine what awaits as they grow further. Today I removed them from the tank, to restore some degree of peace in there. No plants were touched by the Heroinas. They are beautiful and interesting creatures, but I will need to house them in a slightly different set-up.