Can Electric Blue Johannii and Reticulated Hillstream Loach Live Together?

Reviewed by Guidarium Editorial DeskUpdated May 4, 2026
Not Recommended

Electric Blue Johannii and Reticulated Hillstream Loach 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

Electric Blue Johannii

Pseudotropheus johannii

Reticulated Hillstream Loach

Sewellia lineolata

🐠Family Group
Electric Blue Johannii
Cichlids - African
Reticulated Hillstream Loach
Loaches
Temperament
Electric Blue Johannii
Aggressive (8/10)
Reticulated Hillstream Loach
Mostly Peaceful (3/10)
Temperature
✓ Compatible
Electric Blue Johannii
24–28°C
Reticulated Hillstream Loach
20–24°C
pH Range
✗ No overlap
Electric Blue Johannii
7.8–8.6
Reticulated Hillstream Loach
6.5–7.5
Hardness (dGH)
✓ Compatible
Electric Blue Johannii
10–25
Reticulated Hillstream Loach
4–15
Water Type
✓ Compatible
Electric Blue Johannii
Freshwater Only
Reticulated Hillstream Loach
Freshwater Only
Flow Preference
✓ Compatible
Electric Blue Johannii
Moderate
Reticulated Hillstream Loach
High
Min Tank Volume
Combined: 200 L
Electric Blue Johannii
150 L
Reticulated Hillstream Loach
80 L
Swimming Level
Shared: 1 zone
Electric Blue Johannii
MiddleBottom
Reticulated Hillstream Loach
Bottom
🏷️Behavior Tags
Electric Blue Johannii
Generally AggressiveAggressive to same species/look-alikesTerritorial (Defends specific area)Digger (Disturbs Substrate)Plant DestroyerHyperactive / Fast Swimmer
Reticulated Hillstream Loach
Hyperactive / Fast SwimmerTerritorial (Defends specific area)
Stocking calculator

Can your tank handle Electric Blue Johannii 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.

Electric Blue Johannii
Reticulated Hillstream Loach
Test both in my tank

Behaviour & Temperament

Electric Blue Johannii is a semi-aggressive species (8/10), while Reticulated Hillstream Loach is generally mild-mannered (3/10). This notable difference means Electric Blue Johannii may occasionally assert dominance over Reticulated Hillstream Loach.

Electric Blue Johannii and Reticulated Hillstream Loach both frequent the Bottom (Substrate) region of the setup. This overlap can increase competition for space, so providing ample room and cover is important to keep both species comfortable.

Additional behavioural considerations to keep in mind: Two territorial species may clash over territory, especially in smaller tanks.

Water Parameters

The safe temperature window for both species falls between 24°C and 24°C. Aim for the midpoint of this range (around 24.0°C) for optimal comfort.

The pH requirements of Electric Blue Johannii (7.8–8.6) and Reticulated Hillstream Loach (6.5–7.5) 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 Electric Blue Johannii and Reticulated Hillstream Loach together, plan for an aquarium of at least 200 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.

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: Sand (Sifters), Established Algae (Otocinclus), Smooth Gravel (Sensitive Barbels), Plants - lighly covered. Meeting these requirements will help both species thrive.

Note a potential conflict in setup requirements: Electric Blue Johannii is a plant destroyer, which conflicts with Reticulated Hillstream Loach's requirement for live plants. Compromise where possible or prioritise the more critical need.

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

Electric Blue Johannii and Reticulated Hillstream Loach 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 Electric Blue Johannii and Reticulated Hillstream Loach.

Show 6 more tank sizes

Frequently Asked Questions

Can Electric Blue Johannii and Reticulated Hillstream Loach live together?

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

What size tank do Electric Blue Johannii and Reticulated Hillstream Loach need?

A minimum of 200 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 Electric Blue Johannii and Reticulated Hillstream Loach together?

Keep the aquarium between 24°C and 24°C. A target of around 24.0°C sits comfortably within both species' preferred ranges.

Are Electric Blue Johannii or Reticulated Hillstream Loach aggressive?

Electric Blue Johannii is semi-aggressive (8/10) and Reticulated Hillstream Loach is generally mild-mannered (3/10). The gap in aggression levels means the calmer fish may experience stress from the more assertive one.

What pH do Electric Blue Johannii and Reticulated Hillstream Loach need?

Their pH requirements do not overlap. Electric Blue Johannii prefers 7.8–8.6, while Reticulated Hillstream Loach needs 6.5–7.5. This makes them incompatible in the same water chemistry.

How do I manage Electric Blue Johannii's territorial behaviour?

Provide line-of-sight breaks using rocks, driftwood, and dense planting. A larger tank gives Electric Blue Johannii 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 4, 2026
Last updated
May 4, 2026
Issues or corrections?
Contact the editorial team

Related Comparisons

Electric Blue Johannii & Afra Cichlid

·

Possible with Caution
Electric Blue Johannii: PeacefulAfra Cichlid: Peaceful

Electric Blue Johannii & African Jewel Cichlid

·

Not Recommended
Electric Blue Johannii: PeacefulAfrican Jewel Cichlid: Peaceful

Electric Blue Johannii & Altolamprologus Compressiceps

·

Possible with Caution
Electric Blue Johannii: PeacefulAltolamprologus Compressiceps: Peaceful

Electric Blue Johannii & Auratus Cichlid (Mbuna)

·

Possible with Caution
Electric Blue Johannii: PeacefulAuratus Cichlid (Mbuna): Peaceful

Electric Blue Johannii & Aurora Yellow Mbuna

·

Possible with Caution
Electric Blue Johannii: PeacefulAurora Yellow Mbuna: Peaceful

Electric Blue Johannii & Black Diamond Cichlid

·

Possible with Caution
Electric Blue Johannii: PeacefulBlack Diamond Cichlid: Peaceful

Reticulated Hillstream Loach & Hillstream Loach

·

Possible with Caution
Reticulated Hillstream Loach: PeacefulHillstream Loach: Peaceful

Reticulated Hillstream Loach & Mottled Loach

·

Possible with Caution
Reticulated Hillstream Loach: PeacefulMottled Loach: Peaceful

Reticulated Hillstream Loach & Phuket Loach

·

Possible with Caution
Reticulated Hillstream Loach: PeacefulPhuket Loach: Peaceful

Reticulated Hillstream Loach & Spotted Hillstream Loach

·

Possible with Caution
Reticulated Hillstream Loach: PeacefulSpotted Hillstream Loach: Peaceful

Reticulated Hillstream Loach & Angelicus Botia

·

Possible with Caution
Reticulated Hillstream Loach: PeacefulAngelicus Botia: Peaceful

Reticulated Hillstream Loach & Banana Loach

·

Possible with Caution
Reticulated Hillstream Loach: PeacefulBanana Loach: Peaceful