I’ve never had an aggressive one either. Tank size is everything w/ them and tankmates. They will be aggressive in a 4’ tank for sure. A 75g would not be enough space for her to have cichlid tankmates. I’ve mostly kept them w/ thorichthys. Most the time the meeki would be chasing the salvini around, but never any issues. That’s a 6’ 150g. Bet most who have had aggression issues were in smaller tanks.The luck you had with no aggression from the salvini is beyond my comprehension of words.