I have an idea but want to hear from others to confirm or deny my suspicions. Sorry for the photo quality, small fish in a big tank. I've got it on 3 out of 13 fish (one godmani and two snook). I noticed it immediately on the godmani and one snook after putting them into the tank out of the bag they were shipped in. It's a "new" tank (seeded from an existing setup I have) and the only fish in the tank are from this shipment.
On the godmani's dorsal and caudal fin, and a spot on the left side.
Visible on all three places; and on the rear of the snook dorsal in the background.
Visible on godmani dorsal and anal fin and snook dorsal fin and caudal peduncle.
Snook dorsal fin, and other side of caudal peduncle.
On a different snook on caudal fin and dorsal fin
On the godmani's dorsal and caudal fin, and a spot on the left side.
Visible on all three places; and on the rear of the snook dorsal in the background.
Visible on godmani dorsal and anal fin and snook dorsal fin and caudal peduncle.
Snook dorsal fin, and other side of caudal peduncle.
On a different snook on caudal fin and dorsal fin