Can Head and Tail Light Tetra and Neolamprologus Similis Live Together?

Reviewed by Guidarium Editorial DeskUpdated May 6, 2026
Not Recommended

Head and Tail Light Tetra and Neolamprologus Similis are not recommended as tank mates due to conflicting pH requirements. Housing these species together is likely to result in stress, health problems, or direct harm to one or both fish.


At a Glance

Head and Tail Light Tetra

Hemigrammus ocellifer

Neolamprologus Similis

Neolamprologus similis

🐠Family Group
Head and Tail Light Tetra
Characins
Neolamprologus Similis
Cichlids - African
Temperament
Head and Tail Light Tetra
Peaceful (1/10)
Neolamprologus Similis
Semi-Aggressive (6/10)
Temperature
✓ Compatible
Head and Tail Light Tetra
24–28°C
Neolamprologus Similis
24–27°C
pH Range
✗ No overlap
Head and Tail Light Tetra
6–7.5
Neolamprologus Similis
7.8–9
Hardness (dGH)
✓ Compatible
Head and Tail Light Tetra
4–15
Neolamprologus Similis
10–25
Water Type
✓ Compatible
Head and Tail Light Tetra
Freshwater Only
Neolamprologus Similis
Freshwater Only
Flow Preference
✓ Compatible
Head and Tail Light Tetra
Moderate
Neolamprologus Similis
Moderate
Min Tank Volume
Combined: 60 L
Head and Tail Light Tetra
60 L
Neolamprologus Similis
38 L
Swimming Level
✓ Different zones
Head and Tail Light Tetra
MiddleTop
Neolamprologus Similis
Bottom
🏷️Behavior Tags
Head and Tail Light Tetra
Nano / Bite-sized (Predation Risk)Hyperactive / Fast Swimmer
Neolamprologus Similis
Nano / Bite-sized (Predation Risk)Territorial (Defends specific area)Digger (Disturbs Substrate)Aggressive to same species/look-alikes
Stocking calculator

Can your tank handle Head and Tail Light Tetra and Neolamprologus Similis?

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.

Head and Tail Light Tetra
Neolamprologus Similis
Test both in my tank

Behaviour & Temperament

Head and Tail Light Tetra is a peaceful species (1/10), while Neolamprologus Similis is moderately assertive (6/10). This notable difference means Neolamprologus Similis may occasionally assert dominance over Head and Tail Light Tetra.

In terms of spatial distribution, Head and Tail Light Tetra prefers the Middle (Open Water) and Top (Surface) zones, whereas Neolamprologus Similis 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.

Water Parameters

The safe temperature window for both species falls between 24°C and 27°C. Aim for the midpoint of this range (around 25.5°C) for optimal comfort.

The pH requirements of Head and Tail Light Tetra (6–7.5) and Neolamprologus Similis (7.8–9) do not overlap, making it impossible to satisfy both species simultaneously.

For general hardness, the shared comfort zone is 10–15 dGH. Regular testing will ensure conditions stay within this range.

Tank Setup

To house Head and Tail Light Tetra and Neolamprologus Similis together, plan for an aquarium of at least 60 litres with a minimum length of 60 cm. This recommendation combines the stricter species minimums with a community-load allowance so the pairing has realistic long-term space and filtration headroom.

Providing a mix of open swimming space and sheltered areas with rocks, driftwood, or plants will keep both species comfortable and allow natural behaviour.

Specific environmental needs for this combination include: Plants - Densely covered, Leaf Litter/Blackwater, Sand (Sifters), Shells (Breeding/Hiding). 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 Usually Fails in Practice

Head and Tail Light Tetra and Neolamprologus Similis are the kind of pair that can look acceptable in a shop but become a maintenance problem at home. The main risk is not a single number in the chart; it is the way incompatible behavior, water needs, or pressure on space compounds over time once both fish are established in the same tank.

Suitable Tank Sizes

Standard aquarium sizes large enough for both Head and Tail Light Tetra and Neolamprologus Similis.

Show 19 more tank sizes

Frequently Asked Questions

Can Head and Tail Light Tetra and Neolamprologus Similis live together?

No. This combination is not recommended. Key incompatibilities — such as critical behavioural conflicts — make cohabitation unsafe.

What size tank do Head and Tail Light Tetra and Neolamprologus Similis need?

A minimum of 60 litres (tank length at least 60 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 Head and Tail Light Tetra and Neolamprologus Similis together?

Keep the aquarium between 24°C and 27°C. A target of around 25.5°C sits comfortably within both species' preferred ranges.

Are Head and Tail Light Tetra or Neolamprologus Similis aggressive?

Head and Tail Light Tetra is peaceful (1/10) and Neolamprologus Similis is moderately assertive (6/10). The gap in aggression levels means the calmer fish may experience stress from the more assertive one.

What pH do Head and Tail Light Tetra and Neolamprologus Similis need?

Their pH requirements do not overlap. Head and Tail Light Tetra prefers 6–7.5, while Neolamprologus Similis needs 7.8–9. This makes them incompatible in the same water chemistry.

How do I manage Neolamprologus Similis's territorial behaviour?

Provide line-of-sight breaks using rocks, driftwood, and dense planting. A larger tank gives Neolamprologus Similis 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
May 6, 2026
Last updated
May 6, 2026
Issues or corrections?
Contact the editorial team

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