I wouldn't say the odds are one in a million, they're better than that, but as he said it depends on the individual fish, also will depend on what you keep with it. A me,her here has kept multiple different jardinis in a 180g and everyone had tankmates, only thinwas each one had different tank mates because each one would tolerate different things, he was able to keep a large ornate bichirs he had with all of them, and I believe he did have a trachy trachy with 2 of them. If you wanna do a jar comm, best do fish he won't find as a threat, try bottom dwellers, bichirs, catfish, avoid mid-top dwellers, though in a tank like that I'm sure you could get away with some SD or something of that nature