Congrats, he's looking a LOT better!
I've raised several FH over the years, and due to them being susceptible to gastrointestinal issues my recommendation has always been to keep things as simple as possible when it comes to feeding, and be careful about overfeeding. One of my recommendations for most fish, certainly FH, is to make sure they get some aquatic based plant matter in their diet. One of my go to foods in that area is NLS AlgaeMax.
Good luck with him, hope that he keeps doing well.