Hillstream Loach
Sewellia lineolata
Also known as Reticulated Hillstream Loach, Butterfly Loach, Tiger Hillstream Loach
Edited by Ivan F. · Reviewed
Beginner verdict
A small, flattened loach shaped like a tiny stingray that clings to rocks in fast, oxygen-rich water. It needs strong flow, cool temperatures and a mature tank with plenty of biofilm, so it is not a typical community fish. Set up a river-style tank and it thrives.
Care at a glance
- Min tank size
- 18 US gal
- Footprint
- 30 x 12 in
- Temperature
- 68–75 °F
- pH
- 6–7.5
- Hardness
- 1–10 dGH
- Swim zone
- Bottom
- Min group
- Single fish
- Lifespan
- Not well documented
Hillstream Loach care mistakes to avoid
The mistakes beginners most often make with this species.
- Plan on one as the centerpiece of the tank, and read the tank-mate lists before adding others.
- Provide strong flow. It needs clean, fast, well-oxygenated water.
- Keep the water cool, because warm tanks hold less oxygen and stress it.
- Add it only to a mature tank, since it grazes biofilm that new tanks lack.
- Check your tank before you buy. Our sourced minimum is 18 US gallons.
Hillstream Loach tank mates and swim zone
Bottom
Spends most of its time in this part of the tank.
Paracheirodon innesi
Hyphessobrycon amandae
Hyphessobrycon herbertaxelrodi
Trigonostigma heteromorpha
Danio rerio
Tanichthys albonubes
Paracheirodon axelrodi
Their temperature ranges barely overlap, so you will have little room for error.
Hemigrammus erythrozonus
Their temperature ranges barely overlap, so you will have little room for error.
Boraras brigittae
Chili Rasbora is small and shy, and is easily outcompeted for food by Hillstream Loach.
Trigonostigma espei
Their temperature ranges barely overlap, so you will have little room for error.
Ancistrus cirrhosus
Their temperature ranges do not overlap, so one of them would always be stressed.
Mikrogeophagus ramirezi
Their temperature ranges do not overlap, so one of them would always be stressed.
Melanotaenia boesemani
Their temperature ranges do not overlap, so one of them would always be stressed.
Hillstream Loach feeding and care
How to feed
- Let it graze biofilm and algae on smooth rocks and glass.
- Add algae wafers and small frozen foods such as daphnia.
- Feed small portions you can see finished within a couple of minutes, because overfeeding fouls the water fast.
Telling males from females
Best judged from above: females have a broader, rounder body, while males look slimmer with a blunter head.
Plants that suit it
Species facts
- Family
- Gastromyzontidae
- Native to
- Vietnam
- Adult size
- 2.6 in (6.5 cm)
- Temperament
- Peaceful
- Social needs
- Solitary/Centerpiece
- Diet
- Algae Grazer
- Water flow
- High Flow
- Substrate
- Smooth Gravel
- Live plants
- Mostly Safe
- Shrimp
- Adult Shrimp Only
- Fin nipping
- None
- Vulnerable to nippers
- No
- Breeding
- Difficult in Home Tanks
Hillstream Loach FAQ
What size tank do Hillstream Loaches need?
Our sourced minimum is 18 US gallons (68 liters), with a footprint of 75 x 30 cm. A bigger tank is always easier to keep stable.
How many Hillstream Loaches should I keep?
One is fine in a tank this size. Add more only with plenty of extra room and cover.
What can live with Hillstream Loaches?
Good matches on our list include Neon Tetra, Ember Tetra and Black Neon Tetra. Avoid Endler's Livebearer and Molly.
How long do Hillstream Loaches live?
Lifespan is not well documented for this species. Stable water and a good diet help any animal live longer.
Can hillstream loaches live in a normal community tank?
Only if the tank has strong flow, cool water and high oxygen. Most warm, gently filtered community tanks do not suit them.
Where to buy Hillstream Loach
Stores that list it under the same scientific name as this page. We earn nothing from these links. We have not bought from them, so check each store's own terms.
We have not found a store that sells Hillstream Loach under its scientific name yet. We add stores as we confirm them.
Live animals and plants travel by courier. Check the store's live-arrival guarantee, and only buy once your tank has cycled (see how to cycle a fish tank).
Some US states restrict certain species. Check our US state aquarium rules table and your state's own rules before you buy.
Complete the tank
A forgiving setup with room for a small community.
Tank size for this species
At least 18 US gallons (68 L), 75 x 30 cm footprint
Filter
Hang-on-back or large sponge filter
Easy to maintain and strong enough for a community without blasting the fish.
We are still choosing products for this.
Heater
Adjustable heater, about 5 W per gallon: 100 W at 20 gallons, about 150 W at 29
Enough power to hold a stable temperature in most homes. Size up for a cold room.
We are still choosing products for this.
Water Conditioner
Dechlorinator such as Seachem Prime
Tap water contains chlorine or chloramine that harms fish.
Seachem Prime US
Fritz Complete Water Conditioner US
API Betta Water Conditioner US
sera aquatan Spain
Tetra AquaSafe Spain
Maker's page · Sold at Kiwoko · Sold at Tiendanimal · Sold at zooplus.es
Why we chose these (Best Water Conditioner for Betta Fish). Nobody here has used or tested them.
Test Kit
Liquid kit such as API Freshwater Master
Tracks ammonia, nitrite, nitrate and pH while the tank cycles.
API Freshwater Master Test Kit US
API General & Carbonate Hardness Test Kit US
Maker's page · Sold at The Shrimp Farm · Sold at Bulk Reef Supply
sera aqua-test box (Cl) Spain
JBL PROAQUATEST COMBISET Plus NH4 Spain
Why we chose these (Best Test Kit for a Freshwater Aquarium). Nobody here has used or tested them.
Cycle the tank before adding animals. See our guide on how to cycle a fish tank.