easy way to find out if it is flukes of any kind do a fresh water dip the flukes will come off as they will explode kind of in the fresh water there body can not adjust to the water change. they will either float on the top or sink to the bottom depending when you look for them. If they have just come off the fish they tend to float for a few seconds and then drop to the bottom remove the fish and place in a container with salt water in it to let the fish get rid of any of the flukes that died in his gills. if they are open sores then you can use melifix to help the fish heal. I have used it and it helps.

BIll