Can’t seem to get rid of this fungus. Please help.

[Flyin Jawaiian]

Aloha everyone, I’m having this problem it’s been about a week now, it first started off with little white patches on a few of my orange laser corys, I started to treat them with Hawaiian hillbilly’s BSD treatment but after daily water changes everyday on the third day directions say to take a day break so after the fourth day I noticed the fish still had the fungus in their fins and a few more fish had it. I retired the dosage again for another three days and still to no sign of improvement. I’m noticing there’s more of what looks like fungus growing on the fish’s barbels now too I’m not sure if this is from then digging into sharp substrate which I thought wasn’t true, or the fungus is spreading even more. If anyone has any idea what else could cure or help this that would be awesome! 

[Colu]

I would recommend treating with API fungus cure if you can get holed of that you could try aquarium salt as @Tankseeker has suggested if your using aquarium salt I would start as a low dose of 1 table spoon for 5 gallons and gradually increase it over a couple of days to 1 table spoon for 2 gallons as their scale less just keep a close eye on them when using salt if their showing any sign of de-stress I would do water change to remove the salt