Hello! Hoping someone might be able to help with this. I've got a 30lr tank, fully set up with two small ember tetras in (there were more but unfortunately they've gone now.) Last minute I've been given some emperor tetras from a friends fully set up and healthy tank. Are these suitable to have together?? I didn't realise how much bigger the emperor's were going to be until I got them next to the others by the tank. Thanks in advance!