Butterfly Hillstream Loach

Butterfly Hillstream Loach (Beaufortia kweichowensis) The Butterfly Hillstream Loach is the most widely kept hillstream loach in the hobby — immediately recognizable by its dramatically flattened, disc-like body with wide, wing-like pectoral fins spread flat against rocks, creating a silhouette that genuinely resembles a butterfly or stingray. The pale body is marked with a complex pattern of dark brown spots and mottling on a cream to tan background. Suction-cup modified fins allow it to cling to rocks and glass in torrential flow.

Feeding & Care Tip: Live algae and biofilm growing on rocks and glass are the primary food source — see the algae requirement note above. Supplement with Hikari Mini Algae Wafers placed directly on rocks and blanched zucchini or spinach. Hikari Frozen or Freeze-Dried Baby Brine Shrimp can be offered very sparingly as an occasional protein supplement. Strong water flow and high oxygenation are as important as food for these fish.

⚠ Algae & Biofilm Requirement: Like Otocinclus catfish and Stiphodon gobies, hillstream loaches and Borneo suckers are specialized algae and biofilm grazers. They cannot survive without established live algae and biofilm growing on rocks, glass, and hardscape. A tank without significant algae growth will not support these fish regardless of supplemental feeding. Allow algae to establish thoroughly before adding hillstream loaches. Hikari Mini Algae Wafers placed directly on rocks and blanched vegetables supplement but do not replace live algae and biofilm growth.

Native to fast-flowing, clear, well-oxygenated mountain streams and rivers. The aquarium must replicate these conditions: strong filtration creating significant water movement, high oxygenation, rocky substrate and hardscape covered in established algae and biofilm, bright lighting to encourage algae growth, cool to moderate temperatures, and very clean water with low nitrates. These fish are sensitive to elevated nitrates and should never be added to immature aquariums.

As long as it is kept in a well-maintained, mature aquarium with good biofilm and algae growth as well as high water flow, the Butterfly Hillstream Loach is a hardy and entertaining fish. Keep in groups of three or more — more active and social in numbers. Males may be territorial with each other but are peaceful with other species. Compatible with hillstream loaches of other species, small danios, White Cloud Mountain Minnows, and other cool-water fish.

Algae-covered rocks, smooth pebbles, and good water movement are the key elements of a successful hillstream setup. Strong lighting encourages algae growth — this is the opposite of most aquarium setups, where algae is suppressed. The hillstream aquarium is built around algae, not against it.

Care & Ideal Parameters