I take a fish oil vitamin with the brand name Genuine Health…it’s called Omega 3 Joy. Genuine Health makes a few different formulas with the Omegas in it…..but I have found this one to be the most effective.
That being said, however, I still take Concerta and at this point in my life will not be giving it up anytime soon. 
In my humble opinion, fish oils (especially Omega 3’s) are very beneficial for anyone’s brain. But for it be as effective as the pharmaceuticals……I believe the amounts we take now (about 1200 mgs/day) is likely not nearly enough. If you ever do find your research and an alternative treatment…..please post your info. I’d love to know.