Amara shock dmg w/ melee?

I have seen a few peoples builds stating they are doing shock damage with meleebut I am not seeing how? I see the inc and corrosive from the 2 trees but how do you get shock damage on the hits? I have illuminated fists but maybe I am missing something?

Shock damage is the default elemental damage you start off. You can change to inc and corr when leveled up if you prefer

ok, Thanks!

I believe you have to press triangle and then go over to the element and press X it will unequipped fire or corrosive and turn back to shock