Thank you all for your advice!
Bartian – it were no publications on other anabantoids, I indeed read it in special publications on Parosphromenus. I know that many Betta species are very “jumpy”. My Badis species live in completely filled tanks without any covers – they don’t like to come close to the surface, not even to catch floating food – and I am sure they won’t jump. It’s more likely that sometimes a shrimp will jump out – the Red Cherries are the jumpiest.
But ok – I will put a lid on my new Paro-tank. As I don’t like to cut off the water surface from fresh air, I will cover a self-built frame with fly screen and put it on the tank.