I would so a quick FW
dip.. They should fal off really quick.. I had black ick at one point in time and the black spots fell off so quick when i did a FW
dip and I havent seen them since.. That was 6 months ago.. However if they return after a dip i dont know if the same rules apply as in Ich.. If doing a FW
dip make sure the temp and pH are as close to being matched as possible.. Baking soda should be ok to use to match the pH.. Watch your fish for Severe signs of stress.. just an FYI
I have never left my fish in a FW
dip for more than a min or 2.. I would watch them and as soon as you see the spots drop off pull them out and place them back into the tank..