I personally would not put those 3 cichlids together in the same tank.
I find salvini are the most aggressive of the 3.
Cubans have been a close 2nd for me, and although they might be good in salvini temps, but I keep carpintus a tad cooler being from parts of northern Mexico where night time water temps are less warm. Cubans are also the only cichlid in their habitat, so this suggests keeping them in a community of cichlids (at least to me), is not ideal.
I have often held my carpinyus at temps between 68 and 72, and at times seasonally even cooler. I would not subject tetracanthus to that, better 78ish.
But I agree agree with the others who say, they may work growing out, but as adults is when the problems would start.
A 90 might be good for a pair, of any of the 3, just doubtful as a community, in my experience.