Judging appetite in a fish you rarely see eat
A kuhli loach needs a vet when it fails to come out for food across several nights, because absence at the nighttime feeding is the real appetite signal for this species. Kuhlis hide through the day and forage after lights-out, weaving through plants and substrate for scraps, so a daytime glance tells you almost nothing. The concern is a loach that once appeared reliably at dusk and now stays buried, or one that emerges but ignores sinking food dropped beside it. A kuhli seen out in bright light, thin and restless, is showing two changes at once and should not be dismissed as suddenly braver.
Why a kuhli loach may miss its night feedings
A kuhli loach most often misses meals because the food never reaches it, since faster midwater fish clean the surface and mid-levels long before anything sinks. Fine flake that dissolves on the way down leaves almost nothing for a bottom feeder. A lone kuhli is another common factor, because these loaches feed more boldly in a group of their own kind and stay buried when kept singly. Coarse, sharp substrate that irritates the belly and barbels can also keep a kuhli tucked under cover instead of foraging across open ground at night.
How to check a kuhli loach is actually eating
Check a kuhli loach by feeding the tank after the room darkens, using a small sinking pellet or wafer dropped near its known hiding spots. Return with a dim red or low light after twenty minutes and watch whether the loaches snake out and work along the bottom. Note how many appear, because a group that shrinks night by night is information, not just a headcount. If one kuhli comes out, guide food close to it with a turkey baster so it eats without competing, and observe whether it takes the food or mouths it and drifts away.
Kuhli loach signs that call for a vet
Call an aquatic vet when a kuhli loach shows a pinched, hollow look behind the head, faded banding, or damage around the mouth and whisker-like barbels. A loach that emerges in daylight and hangs near the surface or filter, rather than hugging cover, is behaving against its instincts and needs prompt attention. Complete refusal of food placed directly beside it for several nights, especially in a fish you can see is losing condition, moves this beyond a feeding-routine problem. Small, soft-bodied fish like kuhlis carry little spare weight, so waiting for obvious wasting wastes the window to help.
Giving the vet a useful kuhli loach history
Give the vet the nighttime picture, because a kuhli loach case hinges on details a daytime visit cannot show. Record when the loach last fed, what sinking foods you offer, how many kuhlis share the tank, and whether the substrate is sand or gravel. A short phone video of the tank after dark, showing the loach's movement and body shape, is worth more than a description. Logging those dusk observations, water results, and group changes in KinsLe's Pet Passport turns scattered late-night checks into a clear record the vet can actually work from.