Wow, can't believe that worked with the GT! I have kept cichlids ever since I had my first tank with my dad. I completely understand what happens with their behavior. I actually keep Cories with an Oscar for YEARS! Never an issue.If they can fit in someone's mouth they will be eaten. Jacks get some size. Cichlids 'attitudes' get worse with size. The opinion on the Jaguar is definitely right on. With your other fish there will be fighting you will just have to decide how much you will put up with. Some torn fins here and there, missing a scale, a fat lip... it's to be expected but you'll definitely know when someone was pushed too far they will look really ragged.
I don't mean to sound patronizing I simply want to share my experience to see if you could take something away from it. But I had a 125 with mixed cichlids a like green terror, Oscar, Jack Dempsey, Salvini, fire mouth you know the starter cichlids. It worked for a while and then The green Terror put some size on and claimed the return of my FX6. Anything they got near the return was attacked including me. So I netted him put them in a plastic tote time out tank for three days no lights. Then I did some reading on here and on other forms and I decided to lower my tank temperature to 78° instead of 80 and started feeding three times a day instead of two times a day. that tank was that my favorite tank all the way up until I moved and I rehomed everything in it.
What I'm getting at is be prepared for a lot of trial and error something she going to work somethings are going to not work as you're experiencing with your jaguar. It's part of what makes cichlids interesting at least for me. Just a word of warning though what works now might not work a week from now or two months from now. Or it might just watch for territories and observe the push and shove. If you were unlucky enough to have a fish claim the whole tank you'll probably have to rehome.
Correct me if I'm wrong, this is just my theory. Obviously it does not apply to all fish, but semi-aggressive and down I feel like it does.... If a fish grows up with another fish, it'll never be looked at as food. My Cories have been with my Oscar since he was less than 2inches! I know this sounds bad, but again, he could eat 2/3 of them right now. He's pushing 6 inches. I know he has about 6 more inches of growth but he's behavior (luckily) with the other fish has been incredible.
I've seen similar stocking to mine on YouTube (even with the Jaguar) and it looks like they have no issue. I feel like if you have enough areas to "claim" SA cichlids are fine together.
My expertise in SA cichlids are with Oscars and JDs. I've kept them for over 15 years. I loved the colors on the Jaguar and hunted one down. I heard they are more aggressive than Oscars but I underestimated it. I love the look of the Belly Crawler Pike. I read they are most aggressive to other Pikes, which I'll never have him with another. Other than that, my Pike shares the same type of aggression as my Oscar and JD. My Firemouth is tiny and even can show some attitude! I'm excited for him to grow!
I want an aggressive tank that gets along with community fish (Hoplo catfish, Shovelnose catfish, Royal Pleco). Obviously no Tetras
If you'd like, check out my YouTube channel. The name is the same as my username on here.