Synos are weird they are either more the merrier or 1. Lucipinnis as you've found out like larger groups 7 is a good number. Petricola are the same 5 or more seems to make them happy. Multipunks like a pair or more then 5, 3 one may get killed, 4 the pairs square off from time to time and 5+ seemed to some how keep them all together. Nigrita are loners, as are angelicus, eupterus, valentini (hybrid). I don't know all of the different types of synos and/ or have not kept all but I have had all of those listed above currently and in the past as well as others I could only get 1 of that are not listed. None of the ones that "school " will school with other types. That's all from personal experience. This may not be the normal or even anyone elses experience. Too many variables that may make others school that wouldn't normally but from my experience those that I posted as loners will fight with other synos for territory and hides with in an undescribed territory, possibly with one or both ending up dead.
