I have a yellow Severum. Friend of mine was remodeling his house and gave me a 55 gallon tank with a 8 inch Severum. It is a great looking fish. He said he had it for about 6 years. I migrated the fish to my 60 gallon with my pleco, 3 tiger barb and Leporinus. They all do well with one another. I actually bought a baby Severum about 3 weeks ago.. Its awesome.. The baby does everything the mommy does..
That being said, the severum is not aggresive unless hungry. When she didn't get fed for 3 days, I went from 4 tiger barbs to 3..
Now i have a friend come over and feed her when I'm gone more than 2 days..