A magikarp evolves at lvl 20.
Just for future reference, it doesnt matter which virsion the Pokemon is in, it always evolve at the same lvl.
Stantler does not evolve.
graveler doesnt evolve at a level, you evolve it by trading.
Level 23. 
Level 20.
Level 20
it will evolve at lv. 20.
Your Aron will evolve at level 32 into Lairon.
35
Level 27.
14
Level 20.
Level 55