I did Malawi cichlids for some years and found it often takes some tinkering to achieve/maintain a peaceful tank-- so my theory was if things are going well don't make changes without a good reason (like too many of a species reaching adult size, wanting to try a new species, etc.) My experience with severums is they appreciate a larger tank. They themselves are more peaceful in a larger tank. My opinion, but not a cosmic truth, is if he's doing okay in the larger tank I'd leave him there-- an occasional chase is normal for most cichlids.
I like Gourami Swami's advice and agree on the convicts. Don't know if something like a rainbow cichlid would work, they're smaller than a severum, less aggressive than a convict. I've done 50 gal tanks and the question is whether two roughly similar size/shape cichlids of different species will work with the limited length to the tank. Sometimes it does, sometimes not, another case where it helps to have an option for changing things if something doesn't work.
...From photos I've seen, Jersey looks nice, don't know what kind of weather you get, but I'm a fan of rocky coastline.
I like Gourami Swami's advice and agree on the convicts. Don't know if something like a rainbow cichlid would work, they're smaller than a severum, less aggressive than a convict. I've done 50 gal tanks and the question is whether two roughly similar size/shape cichlids of different species will work with the limited length to the tank. Sometimes it does, sometimes not, another case where it helps to have an option for changing things if something doesn't work.
...From photos I've seen, Jersey looks nice, don't know what kind of weather you get, but I'm a fan of rocky coastline.