Could Flashing, Heavy Breathing, and Hiding in Yoyo Loaches Indicate Gill Flukes?

[emmaorabelle]

Hi all,

I'm hoping someone can help me figure out what's going on with a group of my Yoyo Loaches. I keep them in a grow-out system on my fish farm, and over the last few days, a handful of them have started acting differently.

They're spending most of the day tucked away instead of being out and active. I've also noticed some of them breathing a bit heavier than normal and occasionally rubbing themselves against the tank bottom and PVC pipes. A couple of fish look darker than usual and aren't joining the others at feeding time right away.

I checked the water, and everything seems fine. Ammonia and nitrite are at zero, the temperature is steady, and I haven't made any recent changes to the system. I don't see white spot disease, damaged fins FNF, or any obvious wounds, which is why I'm a bit confused.

Has anyone had loaches show these symptoms before? I'm wondering if this could be an early sign of gill flukes or some other parasite that isn't easy to spot. Any ideas on what I should be looking for would be appreciated.