i wouldnt call them killers but if needed they can stand up for themselves. i have 4 in my african cichlid tank and they havent killed anyone. now if the out fish with fit it its mouth it may become a meal, but they dont really randomly attack.
Thanks for the reassurance.
So my jewels and cons should be safe then -too big to swallow! Not sure what species mine are but they are grey with black spots and have ragged dorsal fins with a long protruding spine.Are syno carnivorous? I thought they had sucker mouths like plecs and have been feeding them catfish pellets.They have grown much bigger and are very active all day so I guess they are getting enough food. Should I feed them meaty food like dried shrimp and dried small fish? Have some dried fish & shrimp in stock for my turtles