bichir for 125

Hellos everyone, I bought this little guy as a Delhezi from my LFS, and he’s around 2.5 inches I believe. I wanted to put him in my 125 Gallon with jack Dempsey and 2 Oscar’s that are all around 4 inches. But as of now I’m growing the bichir out in my 55 with my EBA cichlid and BN Pleco. But...

Which of the smaller upper jaws would do best in a 125. I plan for the tank to only have 4-6 fish so I am looking for one with a good personality that doesn't hide all of the time.