[Pavel Chaloupka]

Dorothee. Some, especially bigger species of cyclops (these mostly occure in summer), may be dangerous when you overfeed and the rest of the nauplii in the empty tank cant find their natural nourishment (like infusoria for example). Then they sometimes attack the fry and may bite it or even kill it. If you feed reasonable amounts in your Paro tanks with plants and substrate, it is not dangerous at all, unless you bring home some Ergasilus (true parasitic copepod that attacks even grown fish). I have seen this only once in my life when I was using a food from pond with fish and I have only seen one specimen. No need to be afraid 🙂