i had a jag and got rid of him. it wasn't that he was violent, but he was just way more aggressive than the Vieja in the tank with him. He spent most of the day flaring up at every other fish, all day, every day, relentless.
It was a fight a day, and when he'd lose, he'd forget about it 2 hours later and go right back to flaring up at everything in the tank,. So, there was just no way he'd accept a role in the tank and live with it. Nah, all day long he was just flaring up, squaring off with all fish.
But he never hurt anybody, no fish ever died or anything, but it was just stressful to watch all day long.
That's just one fish, but, I don't think they're a very good match for a Vieja tank. Probably work out better with Amphs?