In my one 29 I use 100% flourite, substrate ferts liquid ferts and 2 DIY bottles of Co2.
In my other 29 gallon , I use schultz multi-purpose soil conditioner with some gravel mixed in with ferts, DIY Co2(2 bottles) , substrate ferts.
My 55 gallon has just gravel, no Co2, rarely use ferts(except for some Iron). The swords do very good...but very slow growth.
My 10 gallon is reg gravel, no Co2(use flourish excel instead), and just liquid ferts. Plants look nice in this tank, but not like the 29's
So the choice is up to you, and how densly planted it will be. If it is just a couple plants..you may not need to do anything special.