This is a discussion on What is this? within the Saltwater Fish Diseases forums, part of the Saltwater Fish and Coral Reef Tanks category; -->
I know they are not the clearist pics. The fish wont stay still. But it sort of looks like mold on a fish. I ...
I know they are not the clearist pics. The fish wont stay still. But it sort of looks like mold on a fish. I have never seen this on a saltwater fish and want to know what it is. He eats fine doesnt seem tobother him yet. The water parameters are has follows; Ammonia-0,nitrite-0,nitrate-10,phosphate-.1, calcuim-480,salinity-1.024.
I know I know nothing about salt water but this looks like a really deep bruise or a cut from something. Maybe an abrasion from a really hard run with something rough and solid. The coloring looks just like a bruise and the description makes it sounds like it could almost be a scabbed although I don't know if fish can form such a thing. Also, maybe the scales were removed there from a similar incident and the "mold" is the skin protecting it until the scales can be repaired, if it has scales of course.
I see this on trout that have been kept in raceways for 6-8 months and every once in a while you see a brownish spot that turns out to be an injury from jumping and hitting the side of the raceways or the water inlet. In the overcrowded raceways it is not a good sign because they don't ever treat injuries.
Hopefully, if it is an actual injury you can treat it to prevent any infections or to keep it from getting worse.