Every aquarist has struggled at some point with keeping a tank clean. Sometimes the best way to handle this is with bio-control. The best agents for this purpose are scavenging species like catfish, snails, shrimp, and most notably, loaches. Loaches are known for their eel-like, flexible and maneuverable bodies, and heightened senses that make them incredible scavengers. Scouring tank bottoms under concealment of night, these fish exhibit peaceful dispositions and are suitable for nearly any community tank so long as they are kept in with 6 or more conspecifics. Along with being amazing vacuum cleaners, many loaches are quite beautiful in color and patterning. Some of our favorites include Lepidocephalichthys guntea, Schistura mahnerti, and Schistura savona.
Slithering along shallow bottoms of slow moving streams and backwater habitats throughout the Ganges and Brahmaputra river systems is L. guntea. More commonly known as the “Panther Loach”, this species exhibits similar color patterning to black panther morphs of leopards and jaguars. Coloration of this species varies slightly between geographic origins, though most have largely black coloration with remnants of leopard-like spots on their caudal and ventral regions. This loach is a resilient, omnivorous bottom feeder that will adapt to any captive diet, and enjoys tank remnants like algae, crustaceans, and other microinvertebrates by gulping substrate and filtering the refuse through gill slits. In captivity, they can be fed a variety of sinking pellets, supplemented by regular meals of bloodworm, daphnia, and brine. Tanks should be equipped with soft, sandy substrate, rocks, driftwood, and plentiful hiding places to take refuge during the day. Loaches also have a tendency to make their ways into tank filters, so make sure to keep them tightly fit! Particularly resilient to low oxygen levels, panther loaches have specialized lungs in their intestines that allow them to gulp and utilize atmospheric oxygen. Thus, they can be used as indicator species for hypoxia. Tank waters should be maintained with temperatures between 68 and 77°F, with a pH of 6.0 to 8.0, and hardness of 36 to 215 ppm.
Looking for a bit of uniform flare from your loaches? S. mahnerti is the Shania Twain of freshwater tanks. Also known as the “Red Tail Zebra Loach”, these fish rock a zebra print with red forked tails. Endemic to well oxygenated and fast flowing streams of Vietnam, these zebra loaches do best in river-tank setups with sandy substrate, water-worn rocks and sporadic vegetation. Strong filters, or canister filters should be used to mimic their natural habitat, though aquarists should perform 30% water changes weekly. Scavenging on plant matter and invertebrates in the wild, these loaches can be fed omnivore pellets, live and frozen fare, algae or spirulina wafers, and will gulp down debris and algae from tank bottoms. These are great community fish, though if kept in groups under 3, they can become slightly aggressive towards tankmates. Optimal water conditions include temperatures between 73 and 79°F, with a pH of 6.0 to 7.0, and hardness of 83 to 300 ppm.
Another specimen from the Schistura genus, S. savona, calls the Kosi River in northern India home. Their natural habitats consist of shallow, slow-moving, clear waters with sandy and organic detritus substrate. In captivity, they do best in tanks with variable substrate of rocks, sand, and gravel, driftwood, some vegetation, and a powerful filtration unit. This species is somewhat intolerant of organic pollutants, though in the right setup, they are easy to care for, and can thrive for up to a decade. Reaching 2 inches in length, these “Half Banded Loaches” exhibit tan bellies with darkened dorsal regions with semi-circular tan banding. They feed in the classic loach nature, and can be fed with the same guidelines as our prior loach friends. These are an especially peaceful loach species that do well in community tanks, though they will fare poorly when kept with more aggressive bottom feeders from their own genus. Water conditions should be maintained with temperatures between 59 and 75°F, with pH of 6.5 to 8.5, and hardness between 36 and 268 ppm.
Certainly worth the investment in time saved alone, hire your own team of loach cleaners!