Actually that sounds like he doesn't have SBD. The bump is just his swim bladder, which every fish as. On some fish it's more evident while other's it's not. The S shape is probably more of a resting position which some of my fish do regularly and they don't have SBD. I would be concerned if he did the sinking or floating, that
would be SBD. But the S shape is not always indicative of the SBD. In which case, bump up his feeding's to at least 4-5 pellets at each feeding since he looks so darn skinny lol. It's not going to hurt him. Especially since the food seems good.
As for foods, read the first three ingredients to tell if the food is good or not. The first three are the most important as they're listed by weight. What you want to stay away from are fillers such as Wheat, Corn and Soybean. However if Wheat is listed in the first three it's most likely just because it's used as a bonding agent in the food so it's actually not terrible. NLS has two whole ingredients and then just one Wheat filler but it's just the bond so that's what makes it a better food. If your Hikari looks like that then you should be good to go ^_^ I don't know exactly when they changed but I know it was fairly recently as in two years or so.