Cory with...Fungus? Columnaris?

[je.mar.sh]

Please help, added 2 cory cats to my school of 4. Within the week a few my cory cats have gotten these raised white spots that appear fuzzy along their body and at the base of their dorsal fins. I have moved them to a hospital tank, but I'm not sure what I'm dealing with. The cloudy white color of the effected areas has seemingly gone away overnight in the hospital tank 🤔 there is sand in the hospital tank and its getting stuck to the now clear raised spots. I don't think it's columnaris, there's no fuzzy stuff around any mouths. Otto's, Embers and Shrimp that shared the same tank are currently uneffected by whatever this is... they were just fed when the photos were taken, that's what's all over the substrate. But a few days before I saw these spots,  I gave them blood worms and forgot to siphon them out, they were in there like an hour if that could indicate anything. Images are from when spots were initially observed. 

[nabokovfan87]

On 10/21/2022 at 12:05 PM, je.mar.sh said:

Especially in this photo it looks like a wound of some kind.  Is it possible a rock or something fell during maintenance and caused a scrape?

Because you saw fuzz, you're automatically going to want to treat for fungal.  Either following that, or alongside, you'd treat for bacterial to prevent secondary infections.  The go to for me in this scenario would be salt, Ich-X, Maracyn.  I follow the directions on the Maracyn for how and when to dose the Ich-X / Maracyn.  The maracyn says something like "on day 3 change water and dose meds".  So what I do is I follow the volume of 30% WC on the Ich-X bottle and then go ahead and re-dose everything.  I believe Maracyn says 25% water change, Ich-X says 30 before re-dosing.

Aquarium Salt would go in on Day 1, if you decide to use it. 

You could also be looking at something like an anchor worm.  Just something to note and look into.