What are Kuhli Loaches? Kuhli Loaches, also known as Coolie Loach or Prickly Eye are fascinating, slender, eel-like fish that bring unique character to freshwater aquariums. Known for their peaceful nature and nocturnal behavior, they enjoy hiding in plants and exploring the tank’s substrate. Interestingly, Kuhli Loaches have defensive spines near their eyes, to protect themselves from predators. If threatened, they can raise these spines which often get entangled in fish nets or in the mouth of predators. Features Synonyms: Cobitis kuhlii, Acanthophthalmus fasciatus, A. kuhlii Family: Cobitidae Distribution: Indonesia (Java and Sumatra), Malaysia, Singapore, and Thailand. Size: Up to 4in (10cm). Behavior: Peaceful; most active at dusk; feeds at night and hides during the day. Diet: Wide range of foods accepted. How to Set Up an Aquarium for Kuhli Loaches? Kuhli Loaches are quite hardy, but thrive in a well-oxygenated, well filtered tank with fine gravel or sand (they love to burrow!). Although they tolerate a wide range of water parameters, they do prefer soft, slightly water. Water temperatures between 21-24°C is optimal, but wider ranges are tolerated. How to breed Kuhli Loaches? These egg-laying fish do not usually breed in aquariums but have being known to do so infrequently. The eggs are laid below the water surface and stick to the roots and stems of plants.