The thing is, your carpintus is still a baby, once they mature, its an entirely a new territorial ball game.I keep my carpintis in a 125 with a with an angel fish , a few groumi , parrots and small bass , fh, flagtails ,
He’s about 3 inch he’s aggressive but get along with everyone plenty of space nothing is over 3 inch
The one below is only half grown in this pic.

As a full grown adult, it will be ablate snap your gourami, and some others in half, with one bite.
Here is the one in a photo above, a few months later, and around 12".
