GT and blue acara will clash (with the GT being the aggressor) since they look so much alike. There's a smaller version of the blue acara and that's the electric blue acara, but I still would not put it in with a GT. GT's can be hyperaggressive to other species of cichlids as well. The threadfin can be a pain to other cichlids or if there is an aggressor like a GT, lose its nice threadfins.
Sounds like the GT would be an issue for my stocking.
What if I switch out the green terror for a severum, probably the least discussed fish on my original post?
125 gallon
3 FM
1 severum
3 threadfin acara
3 blue acara
small school of bleeding heart/black skirt /buenos aires tetras

