Reticulated hillstream loaches (Sewellia lineolata) are one of the coolest-looking algae eaters, but there’s a lot of conflicting information about their care requirements that makes people hesitant to try them. After more than a decade of owning, selling, and breeding them, this article shares our personal experiences on how to successfully keep this amazing species.

What are Reticulated Hillstream Loaches?

There are many types of hillstream loaches that live in similar environments, but let’s specifically discuss the reticulated hillstream loach (also known as the tiger hillstream loach or gold ring butterfly sucker) because it is one of the most common varieties available in the aquarium hobby. This 2.5-inch (6.4 cm) oddball fish looks like a miniature stingray because of its streamlined shape, flat underside, and horizontal fins that can tightly grip onto any smooth surface. Plus, its unusual body is covered with light-colored spots and dark brown striping patterns. During the daytime, you can often find them climbing on the glass in a side-to-side crawl or fluttering their fins on the ground while searching for food.
The hillstream loach has a highly patterned and streamlined body that is built to grip tightly onto rocks and withstand rushing rapids.

Originally found in tropical regions of Vietnam, Laos, and Cambodia, hillstream loaches live in shallow riffles, river rapids, and slower-moving stream pools in between. Their native habitat tends to have lots of rocks and is sparser in vegetation. Because heavy rainfall can stir up sediment and cause fluctuating water parameters, they are quite hardy and can handle a wide range of environmental conditions.