For the first time, I'm listening about the Jaguar. I've been thinking about this since the post, his aggression has definitely been growing week by week. My Hoplo looks fine, but has been taking a beating. He's tough as nails thank God. Surprisingly he fights back too (my Oscar is actually afraid of the Hoplo lol)
I will definitely take a look at the Loisellei. I'm not sure if any places would have one though. It was very hard to get the Jaguar and that seems even rarer.
I'm going to purposely over feed my Lima and lower the amount of food for my 125. I'll do pellet and flakes/just flakes every other day.
Luckily my tank is my "Oscar's Tank". He's like the warden. He's not aggressive unless there's aggression (started by the Jaguar mostly). He keeps the tank in check. He could easily eat 2/3 of my Cories but doesn't.... He did also grow up with them. That's why I feel like he'd be fine with the Shovelnose when he puts on some size
Anything with parachromis in-front of it is asking for aggression. They are beautiful though. I'd say don't be quick to write off a solo fish for the 125. If you haven't kept a monster that is 11-12 inches yet solo in a tank, it can be quite rewarding if you give it a chance. Set the tank up to compliment the colors you want and it can be a really interesting show piece. I blacked out a 75g tank for one Midas and it was my favorite tank. I also had a pair of Dovii in a 125 for a while until I rehomed them because I just simply couldn't move my 180g tank by myself.