If you want to experiment with a large shoal of small tetras you need to get very small fish as you want to have a large size gap between the tetras and the crenicichla
Of course if you were talking about the option of getting larger tetras then the time it takes for jzx to bring in multispinosa would aid in the tetras’ size development.
Always wanted Agnesae but wasn’t sure if they’d be able to escape predation by pikes of this size. How big have yours gotten at full grown?
I’d like to add to this list: moenkhausia agnesae, astyanax, psaliodon, cyphocharax, leporinus, synaptolaemus, brycon.