My Oscar got the crap beat of him at 5 inches by a 5 inch Jack Dempsey. It was one of the meanest fish i have ever kept, next to the Midas that drew blood after it bit me and latched on to me hand. They are really territorial. Also, I wouldn't mix Jurapari with a meaner cichlid such as a Jack Dempsey. Jurapari are very social fish that should be kept in groups, in your tank I'd say at least 6. Also, they need to have a tank with a sandy bottom, as they shift sand around looking for worms and larvae. Jurapari can have gravel get stuck in their mouths which can cause a broken or dis figuration. The Jack Dempsey will most likely bully them too. If I were you I would get an Oscar, preferably a very small one that you can raise and some Jurarpari or other large sized eartheater and leave the Jack Dempsey alone. I say to get a small because I rescued one from a ten gallon at m y local fish store that somebody couldn't take care of. I brought him home and out of five Oscars, he is as mean as the Jack Dempsey. His previous owner most likely gave him feeders and instilled this urge to hunt and kill. My other Oscars were all gentle giants that would eat pellets. Check out these guys, they would go well in your tank.
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