Can Black Neon Tetra and Reticulated Hillstream Loach Live Together?

Reviewed by Guidarium Editorial DeskUpdated April 28, 2026
Possible with Caution

Keeping Black Neon Tetra and Reticulated Hillstream Loach together is possible but requires caution, though some care is needed. Provide a spacious tank of at least 80 litres with plenty of hiding spots to reduce stress. Monitor behaviour closely, especially during the first few weeks.


At a Glance

Black Neon Tetra

Hyphessobrycon herbertaxelrodi

Reticulated Hillstream Loach

Sewellia lineolata

🐠Family Group
Black Neon Tetra
Characins
Reticulated Hillstream Loach
Loaches
Temperament
Black Neon Tetra
Peaceful (1/10)
Reticulated Hillstream Loach
Mostly Peaceful (3/10)
Temperature
✓ Compatible
Black Neon Tetra
23–28°C
Reticulated Hillstream Loach
20–24°C
pH Range
✓ Compatible
Black Neon Tetra
5–7.5
Reticulated Hillstream Loach
6.5–7.5
Hardness (dGH)
✓ Compatible
Black Neon Tetra
1–15
Reticulated Hillstream Loach
4–15
Water Type
✓ Compatible
Black Neon Tetra
Freshwater Only
Reticulated Hillstream Loach
Freshwater Only
Flow Preference
✓ Compatible
Black Neon Tetra
Moderate
Reticulated Hillstream Loach
High
Min Tank Volume
Combined: 80 L
Black Neon Tetra
54 L
Reticulated Hillstream Loach
80 L
Swimming Level
✓ Different zones
Black Neon Tetra
MiddleTop
Reticulated Hillstream Loach
Bottom
🏷️Behavior Tags
Black Neon Tetra
Hyperactive / Fast SwimmerNano / Bite-sized (Predation Risk)
Reticulated Hillstream Loach
Hyperactive / Fast SwimmerTerritorial (Defends specific area)
Stocking calculator

Can your tank handle Black Neon Tetra and Reticulated Hillstream Loach?

Compatibility is only part of the answer. Test both fish with your real tank size, current stock, and maintenance needs to see if you have enough space and a safe stocking level before you add them.

Black Neon Tetra
Reticulated Hillstream Loach
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Behaviour & Temperament

Black Neon Tetra is a peaceful species (1/10), while Reticulated Hillstream Loach is generally mild-mannered (3/10). This modest difference means Reticulated Hillstream Loach may occasionally assert dominance over Black Neon Tetra.

In terms of spatial distribution, Black Neon Tetra prefers the Middle (Open Water) and Top (Surface) zones, whereas Reticulated Hillstream Loach occupies the Bottom (Substrate) zone. Because they use different levels of the water column, territorial disputes are less likely and the tank will appear more balanced.

To improve the chances of a peaceful coexistence in this community tank: Provide a significantly larger tank (at least 50% more volume than the minimum) to allow both Black Neon Tetra and Reticulated Hillstream Loach to establish separate territories. Add plenty of line-of-sight breaks using driftwood, rocks, and dense planting to reduce territorial confrontations.

Water Parameters

The safe temperature window for both species falls between 23°C and 24°C. Aim for the midpoint of this range (around 23.5°C) for optimal comfort.

Both fish can tolerate a pH between 6.5 and 7.5. Maintaining a stable value within this band is more important than hitting an exact number.

For general hardness, the shared comfort zone is 4–15 dGH. Regular testing will ensure conditions stay within this range.

Tank Setup

To house Black Neon Tetra and Reticulated Hillstream Loach together, plan for an aquarium of at least 80 litres with a minimum length of 90 cm. This recommendation combines the stricter species minimums with a community-load allowance so the pairing has realistic long-term space and filtration headroom.

Because this pairing requires extra vigilance, include plenty of hiding spots — caves, driftwood, and dense plant clusters — so the less dominant fish can retreat when needed.

Specific environmental needs for this combination include: Plants - Densely covered, Driftwood (Digestion/Hiding), Leaf Litter/Blackwater, Smooth Gravel (Sensitive Barbels), Established Algae (Otocinclus), Plants - lighly covered. Meeting these requirements will help both species thrive.

Both species do well with moderate (standard) water movement, so a standard filtration setup rated for the tank volume should suffice.

Why This Pairing Needs Extra Planning in Practice

This pairing usually fails when the tank is treated like a standard mixed community and the caution flags are ignored. Black Neon Tetra and Reticulated Hillstream Loach need extra room, more cover, and closer observation during the first few weeks so small aggression, feeding, or territory issues do not snowball into a long-term problem.

Suitable Tank Sizes

Standard aquarium sizes large enough for both Black Neon Tetra and Reticulated Hillstream Loach.

Show 10 more tank sizes

Frequently Asked Questions

Can Black Neon Tetra and Reticulated Hillstream Loach live together?

They can coexist, but the pairing requires careful monitoring. Provide ample space (at least 80 litres), plenty of hiding spots, and watch for signs of stress or aggression.

What size tank do Black Neon Tetra and Reticulated Hillstream Loach need?

A minimum of 80 litres (tank length at least 90 cm) is recommended. This provides enough space for both species to establish their own areas and reduces the likelihood of territorial disputes.

What water temperature is best for Black Neon Tetra and Reticulated Hillstream Loach together?

Keep the aquarium between 23°C and 24°C. A target of around 23.5°C sits comfortably within both species' preferred ranges.

Are Black Neon Tetra or Reticulated Hillstream Loach aggressive?

Black Neon Tetra is peaceful (1/10) and Reticulated Hillstream Loach is generally mild-mannered (3/10). Their similar temperaments generally lead to a peaceful coexistence.

What pH do Black Neon Tetra and Reticulated Hillstream Loach need?

Both species overlap in the 6.5–7.5 pH range. Consistency is key — avoid sudden swings, and test regularly to stay within this window.

How do I manage Reticulated Hillstream Loach's territorial behaviour?

Provide line-of-sight breaks using rocks, driftwood, and dense planting. A larger tank gives Reticulated Hillstream Loach space to claim a territory without encroaching on the other fish's area. Adding décor that divides the tank into distinct zones works especially well.

Editorial Review

Guidarium Editorial Desk

Reviewed against Guidarium care, stocking, and compatibility standards. Read the editorial policy.

Last reviewed
April 28, 2026
Last updated
April 28, 2026
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