Hiya, I only run two tanks at the moment.
One is a wide three footer (159ltr), which has a real mix of dwarf South American fish - panda and pygmy corys, rocket and golden pencils and possibly only two steel blue cichlids. I did have ember tetras in there, but moved them to the other tank to be dithers.
The second tank is 60 x30 x30 and has 5 bandit corys (Corydorus metae) and the four embers. I will be adding more embers as money allows. I had plans to add another pair of dwarf cichlids too, but may just go with a larger school of embers. Trouble is, they don;t seem to be very hardy. I've bought about 20, but left with four.
I think the shy corys really like both plenty of cover, and also some other fish to make them feel safe.