Hillstream Loach: Ultimate Guide (Care, Diet, Breeding & More)

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Written By Matt Stevens

Hi, I'm Matt! I've been obsessed with fishkeeping for over 15 years now and created this site to share my knowledge with others.

The Hillstream Loach is a unique-looking freshwater fish with an unmatched beauty in the aquatic community.

We may lack the right adjectives to describe its timeless beauty, but if we were to sum up its appearance in just one word, we would call it exquisite.

If you’ve been looking for a neat algae eater with a characteristically streamlined body, the search ends today. You won’t have any challenges keeping Hillstream Loaches in an aquarium, and you won’t be attracted by its beauty alone.

You will love them even more after learning about their low-maintenance traits with a calm personality to back it up.

We have always recommended these fish to aquarists of different levels and individuals who can maintain the right water parameters to help them thrive in their new environment.

And in this guide, we will be providing everything you need to know about Hillstream Loach care. Is it true that they thrive in colder conditions? Can you pair them with the popular Rasboras? Or, is breeding them even possible in the first place?

This guide will be covering important details about the amazing Hillstream Loach, including care guidelines, tank mates, tank size, breeding, and much much more!

Species Overview

The Hillstream Loach, with the scientific name, Sewellia lineolata, belongs to the Balitoridae family. Like many loaches, they are inhabitants of fast-flowing Asian rivers and streams that have been located in India, Southeast Asia, China, and Vietnam.

Their strong liking for fast-flowing water explains their distinctive appearance. And with a characteristic hydrodynamic drag, they won’t be stopped by anything in the wild. Not even strong water currents.

You will likely spot them steadily scavenging for food at the bottom half of the stream or relaxing on a smooth rock in the wild.

ColorLight yellow-grey, with black bands
Lifespan8-10 Years
Care LevelEasy
Behavior & TemperamentPeaceful community fish
CompatibilityPeaceful, non-aggressive fish
Food and DietOmnivores
Size2-3 Inches
Tank SetupPure, well-oxygenated water
Tank Size (Minimum)50 Gallons


A typical Hillstream Loach will have an average lifespan of 8-10 years with proper care. Like any other fish species, their typical lifespan will depend on several factors, most notably, the level of care in the aquarium.

If you intend to keep them in a home aquarium, your biggest worry will be the ideal water parameters. But don’t worry, we will be covering that shortly.


Turns out the ease of care is not the only reason you will fall in love with these amazing marine animals. If you were to see them in their natural habitat, you would easily fall in love with them at first sight.

With their captivating look, many aquarists confuse Hillstream Loaches with catfishes at first sight. In our opinion, these fish exemplify natural beauty, which starts with colorful patterns throughout their bodies.

They boast a characteristic light greyish or yellow coloration, with random black shades supplementing the original color. Their nicely shaped bodies give them the hardcore trait. And they are not one to be shaken by fast-flowing waters.

They can swim through fast-flowing waters without worrying about strong currents. Still, on appearance, the reticulated Hillstream Loaches possess distinctive pelvic and pectoral fins that are wing-shaped.

This is especially important for added protection in the wild. If you don’t look keenly at their bellies, you won’t even notice their sucker mouths and the flat bottom. 


Hillstream Loaches are small-sized, only ever reaching 2-3 inches in length throughout their lifespan. You don’t have to worry about their size because these fish will do enough to capture your attention.

In captivity, you will usually see them at the center of everything happening inside the tank. Often, they will be relaxing on the added rock surfaces or the side of the tank.

Hillstream Loach Care

Hillstream Loach care guidelines are pretty much the same as in most other fish species. It has everything to do with improving water quality by first monitoring the fish’s eating habits, comfort, and natural habitat.

Hillstream Loaches are extremely rewarding species if you maintain the right tank conditions. And any design idea must incorporate the fish’s original habitat in Asia.

This means everything from water temperature to pH levels and hardness must suit the standard levels. We will discuss that in detail in the following paragraphs.

Tank Size

Now, this will surprise you. The standard tank size for a typical Hillstream Loach is about 50 gallons. If you are wondering how that’s so, we’ll tell you why.

To make it clear, Hillstream Loaches thrive when kept in a community, usually in groups of 3-4. Besides, these fish species require proper aeration and the right water flow to thrive.

Proper water flow, in particular, is vital to the survival of the Hillstream Loach and is the only reason we don’t recommend small tanks when keeping them at home. You won’t create and maintain a consistent and undisrupted water flow in a small tank.

Besides, opting for a powerhead to increase the water current may not save the situation. Usually, aquarists place much emphasis on water flow because oxygen is essential. So, with reduced flow, you will be depriving them of a basic need for survival.

Water Parameters

Hillstream Loaches are best kept in cooler water. However, the standard water parameters are pretty much the same as most other freshwater fish species. They usually thrive if you maintain everything at the following levels:

  • Water temperature: 68°F and 75°F
  • Water hardness: Medium to hardness
  • pH Levels: 6.5-7.5

Experienced aquarists understand that the best way to control shifting water conditions is through regular testing. And you can simplify everything for your Hillstream Loach by detecting early shifts before anything gets out of hand.

As part of the strict adherence to the standard water parameters, regular water changing should be a habit when it comes to Hillstream Loach care.

Changing the water at least once every week is the first step to keeping the diseases away and giving your Hillstream Loaches the ideal conditions for survival. 

What to Put in Their Tank?

As famous bottom dwellers, Hillstream Loaches benefit from a sandy or soft substrate. This also provides added protection given their smooth bodies that are susceptible to cuts and injuries.

In captivity, these fish require the perfect resting spot when they are not on their regular search for food.

Another important element to include in their tank are smooth rocks. These prove vital for constant algal growth that serves as an essential food source to your Loaches.

Also, you should introduce the right hiding spots made from artificial items or natural live plants. Plants like the Hornwort or the Java Moss are excellent choices to give them security while improving the water quality.

On top of that, you should go for the right decorative elements and unique objects such as driftwoods to complete the tank décor. If you want to design the perfect habitat, don’t be afraid to perform a few simple touches to enhance the tank’s general appeal.

Common Diseases

Hillstream Loaches are not one to be bothered by species-centric diseases in the fish community. However, they can be disturbed by everyday problems that would usually distress most freshwater fish species.

If you notice patchiness in their coloration, strange eating habits, or unusual swimming patterns, you should suspect Patchy disease. This condition is fairly common in Hillstream Loaches and will present them with rapid breathing and discoloration.

At first, you may feel stranded when you first notice the symptoms of Patchy disease in your Hillstream Loaches. But no need to panic if you can get the proper medication to manage it.

Generally speaking, most of the diseases affecting the Hillstream Loach can be classified into bacterial, parasitic, fungal, and viral infections. And you can treat bacterial and fungal infections easily with the right over-the-counter medications.

Sometimes, visible external worms, parasites, or patches in your fish should guide you in selecting the right medication for treatment. Up to this point, we can’t stress enough the importance of maintaining suitable water parameters to sustain your Hillstream Loaches in your fish tank.

Water contamination puts your fish at an increased risk of contracting the most common diseases in the fish community. However, most of these conditions will never be a problem if you maintain a proper diet and pay attention to the fish’s behavior in the aquarium.

Remember that preventing a potentially lethal disease in your species or detecting it at the earliest stage could prove vital to saving their lives. It’s more important than waiting to counter its effects with over-the-counter medicines.

Ich disease is another common condition that will present itself with white spots throughout the fish’s body. To control its spread, you may want to test the water parameters regularly and pay more attention to the fish’s ordinary diet.

It wouldn’t hurt to separate the newly bought Loaches from the general population for a few days before introducing them to the usual habitat to control disease spread.

What do Hillstream Loaches Eat?

Longevity is not a unique term in the fishkeeping community. And if you so badly want to increase your Hillstream Loach’s lifespan, you should provide a balanced diet every day. These fish are the true omnivores who will scavenge for any available food in the wild.

Their love for smooth rocks is linked to their strong appetite for algae, an integral part of their ordinary diet. But in captivity, you should focus on supplementing their algae diet with the right food combinations.

Pellets, flakes, brine shrimp, frozen bloodworms, and algae wafers are handy options to provide essential nutrients for their survival. On top of that, you can introduce them to vegetables such as spinach and kale to be sure their nutritional needs are fully met.

Remember, Hillstream Loaches are not one of the largest fish species in the wild. And even their small body parts will confirm this. So, you don’t have to feed them on large flakes or pellets that they will struggle to eat.

Also, overfeeding is not necessarily a great move when keeping Hillstream Loaches. It could have more harm than good to your cute little buddies.

Behavior & Temperament

Hillstream Loaches are one of the most peaceful fish species you will ever find. They won’t pick random fights with their tank mates and won’t create any disturbance from other species.

If they can’t find algae to feed on in the tank, they will prefer to relax on smooth rocks or the side of your aquarium. You won’t be able to stop looking at them when they attach to the sides of the tank.

However, their peaceful coexistence with fellow Loaches will be threatened when you choose to keep a large number in the same tank.

We recommend a maximum of 3-4 Hillstream Loaches for every 50 gallons because keeping a larger number will almost certainly create endless scuffles.

Hillstream Loach Tank Mates

As we’ve already mentioned, the Hillstream Loach is a peaceful fish that won’t get into unnecessary squabbles with its tank mates. Perhaps they are aware of their small size and know they won’t match most other species of larger sizes.

You will want to focus on behavior when choosing suitable tank mates for your Hillstream Loach. And throughout our experience with these and other fish species, we can’t see better options than the Rasbora species and Danios.

Given that they love colder environments even in captivity, it would be impossible to keep them together with tropical freshwater fish. In summary, these are some of the best options you can keep together with Hillstream Loaches:


Breeding Hillstream Loaches is challenging in captivity but not entirely impossible. And you will have a better chance if you control the water parameters. Usually, it begins with a mating dance from the male Loaches.

For everything to kickoff at this point, the females have to give a seal of approval. Then, the male will be responsible for building the nest and adding the suitable substrates, in the process.

The female will then lay her eggs, but hatching won’t happen until after a few weeks. Luckily for aquarists, Hillstream Loaches are just as caring as you want them to be. So, you don’t have to worry about putting them in a separate tank after breeding.

Final Thoughts

Hillstream Loaches are the good-looking algae eaters every aquarist will want to have at home. Caring for them is pretty straightforward, and we can’t recall the number of times we have recommended them to seasoned aquarists around the world.

Based on their vibrant appearance alone, you will be getting a special pet whose presence in the tank will be addictive to watch the whole day. In our opinion, Hillstream Loaches deserve more attention from the entire fishkeeping community.

And if you decide to give them a try, don’t fail to document your journey throughout their lifespan because it will be one worth keeping in the memory books!