I have a 540 Gallon tank with various types of Vieja, and there is LOTS of aggression, all the time. I can't imagine trying to keep full grown adult Vieja together in a smaller tank.
And then ..... your tank is 5 feet. It would be a better setup if it were 8 feet long, or at least 6. Your tank dimensions make it pretty close to a cube.
What I think would be really cool in that tank is some smaller Central American Cichlids. They look better, they stay smaller, and they're just as mean to each other as the full size Vieja.
Some of the very BEST fish in the hobby are in the 6-8 inch range, and would be a great fit for that tank. Consider:
1. Sajica -- first and top of the list, get 6-8, drop em in that tank, and enjoy the show.
2. Bartoni -- when they breed, their black and white "tuxedo" colors are very cool. Very active.
3. Labridens (Media Luna) -- Yellow Labridens are very cool, very rare, and endangered in the Wild. If you can breed those, you'd be an elite aquarist.
4. Carpintis -- I think they're 10 inches, big for that tank, but the Rio Hondo are electric blue.
5. Multispinosa -- Bright yellow fish, aggressive and very territorial.
6. Clown Loaches -- They'll go in that tank with any of the fish above, they school (kinda), their behavior is fascinating, and there are several different types of loaches besides the Clowns--but Clowns are the best. Clown loaches play dead sometimes in the tank.
Get plenty of stumps and rocks, mix and match some of these species, maybe you can get by feeding sparingly so you won't get a bunch of algae on your plants, you could grow some Anubias in that tank, too?