Your fish looks contsipated, I would recommend adding epsom salt to the tank water as a purgative. If he's still eating, you can also pre-soak your pellets in a 3% epsom salt solution to assit in the purging, and reduce hex/spiro pathogens.
Also, Hexamita/Spironucleus is a flagellate pathogen, and has nothing to do with the little white worms seen in tanks when they are overfed, those worms (planaria) are harmless. The most effective way to remove them from your tank is via water changes, and reduced feeding, as those worms are caused by excessive nutrients, which in turn they feed off of.
I also concur with mangingisda - power feeding is never a good idea, fish do not need to be fed extreme quantities to reach their full potential. This is just another one of those stupid ideas that gets bantered about on the internet by people who are typically fairly ignorant about feeding & raising fish.