I have a single corydoras ambiacus I'm looking for some companions for him but am not having any luck finding any. How likely is it that schwartzi or agassizii would school with him?
they will probably all group together, but there will be times when he is left out. pick one species though and get a nice big group instead of two smaller ones.
All species of corys will school together (from what I can tell). It's better to have a few of each species though. But if you can't find any, having a school of different species is better than having them on their own.