Well, the one in the Middle is definitely an African Tigerfish, Hydrocynus vittata, and the African or Kafue Pike is an African Pike, Hepsetus odoe, and the one on the top is a Gar Characin or Rocket Gar, Ctenolucius hujeta.
I'm not a big predatory fish keeper, but I would bet that the Rocket Gar would be OK in a 120, but that the other two would get too big. I know the Tigerfish is a riverine pelaigic species and needs lots and lots of swimming space. African Pikes get 2 1/2' long, (70cm) according to fishbase, so that's probably too big for the 120. Practical fishkeeping says that a 75 is good enough for 1, but that's based on the fact that the fellow who wrote the article has never kept one that got larger than a foot. On the balance, a 120 ought to work.