I'm glad that the red spots are looking better. I would keep the salt where it is for now. You were never sure that your fish had ich, right?
With the tilting, I'm wondering if you could notice whether or not he is tilting towards a light source? My fish tilts sometimes, and I was told that since I don't use over head lights, she tilts towards where the light source is.
I believe tilting could be a sign of parasites, though.. so it'll be something to keep in mind when the antibiotic treatment is over. Post here again if he's still doing it so a Mod or someone more knowledgeable than me can help you with it.
That was a good idea to clear an area for the food. Be sure to clean the food bits out of the gravel, or they'll rot there and build up bacteria.
Keep us posted.
Debbie