It might be slightly mportant to find out what location variant you are getting (if possible).
Some lepidota are from as far south as Uruguay, and may benefit from a cool down, or at least cooler temps than the average South American tropical fish.
Uruguayan Crenicichla I kept, did fine at room temps (no heater) and seemed to benefit from cool downs as low as high 50sF in winter, although I'm not sure it was absolutely necessary.
I over wintered them in a kiddy pool on the floor of my basement, where temps dropped significantly.
And although I never found them to be aggressive with high bodied fish, the lower temps may have helped temper aggression warmer temps might illicit.