Trimacs are amazing but i dont think a breeding pair will work in a 80g. mine bred in a 75g when they were younger and raised the fry together but now i cant keep them together.
With it only being an 80g tank, I would try to limit the maximum size to around 8-9". Anything bigger or overly aggresive, will most likely end with something tragic. So things like TRIMACS, Red Devils and things of that sort, are prolly to big and aggressive.