White marks on kuhli loach: fungus, columnaris or just scratch?

[koalanoodle]

My striped kuhli loach recently showed up with white patches along it. My first thought was that it was fungus or columnaris since there was a death in the tank while someone was watching it when I was out of town (so lesson learned on that). So a fungus developing in the day or two that the tank wasn't watched seemed like it was the most likely answer.

But the loach hasn't had any change in activity or anything. It still comes out in the morning and still does laps around the tank with the other loaches occasionally. None of the platies in the tank have changed behavior either and none of them show any signs of an infection and I would think that if a fish was going get sick from a dead fish it would be one of them, especially one of the smaller, younger ones. The white patches also look like they follow pretty evenly along the spine so now I'm thinking it could just be a scratch from swimming under something or even just stretchmarks. The one white mark on the bottom is what's making me worried that it could be something else.

Is this something that I should quarantine and start treating or am I worrying over nothing? I have some paraguard and API general cure but if it's columnaris I'm not sure either of those would be effective, so is there something for treating that that people recommend, especially since kuhlis are a bit more sensitive to meds?

[Colu]

What I would do is check your water parameters ammonia nitrite nitrate pH KH GH temperature just in case something off it Could have injured itself getting into a small space because it's a long the spine could also be a bacterial component what I would do is get holed of kanaplex or maracyn2 which every one is more readily available and do a course then give an update 

[koalanoodle]

Update: I was able to get some kanaplex delivered luckily. The size of whatever the patches are haven't changed for better or worse which leads me to believe it may be scratches, but I did a half dose of kanaplex for the whole tank just in case since I'm dealing with scaleless fish. The loach seems to be fine and is eating and active but I'm just going to make sure.

[Colu]

On 12/26/2023 at 2:53 AM, koalanoodle said:

Update: I was able to get some kanaplex delivered luckily. The size of whatever the patches are haven't changed for better or worse which leads me to believe it may be scratches, but I did a half dose of kanaplex for the whole tank just in case since I'm dealing with scaleless fish. The loach seems to be fine and is eating and active but I'm just going to make sure.

Kanaplex isn't effective at half dose and its more likely to lead to antibiotic resistant in my experience full dose of kanaplex is fine for scaless fish

[anewbie]

I would not treat the fish; those look like scrape marks - do you have something sharp in your aquarium or perhaps your substrate is sharp (put some between your finger and squeze and move back and forth). Kuhli love to fit in tight spaces and dig in substrate and if there is anything sharp it will make marks like those. Also kuhli are very sensitive to meds (scale-less fish) and med will likely do more harm than good.