I am sorry for giving poor advice on the auranti. I have seen a lot of aurantis here in ksa being kept in 75 gallons without any issues and hardly exceeding a foot. But a experienced and senior member like RD knows better, so you should listen to him.
Many of my comments here are based on my own stupid mistakes made over the years, including with snakeheads. At some point everyone that is in this hobby for any length of time will come to learn that the smaller the glass box, the more stressed the animals inside. Even with great water quality, which is seldom the case in these situations, the animal will be stressed to some degree, which typically leads to health issues, and a shortened lifespan.
40+ yrs ago when on a road trip in Montana, my friends and I stopped at a roadside zoo. That zoo (cough-cough) had a large, mature male lion. A truly majestic beast, that was living in an enclosure that was maybe 20ft x 20ft. Probably smaller. It was disgusting. Watching an animal like that pace in circles over & over wasn't exactly what I would describe as
thriving in captivity. Just before we left, with my face up near the enclosure, that lion let out a roar so loud & powerful that he must have blown my hair back. I still remember the experience like it was yesterday.
Yet driving away all I could think about, was that it would have been better off if I had put a bullet in its head.