Can Sulphur Crest Lithobates and Threadfin Rainbowfish Live Together?

Reviewed by Guidarium Editorial DeskUpdated May 7, 2026
Not Recommended

Sulphur Crest Lithobates and Threadfin Rainbowfish 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

Sulphur Crest Lithobates

Otopharynx lithobates

Threadfin Rainbowfish

Iriatherina werneri

🐠Family Group
Sulphur Crest Lithobates
Cichlids - African
Threadfin Rainbowfish
Rainbowfish
Temperament
Sulphur Crest Lithobates
Semi-Aggressive (6/10)
Threadfin Rainbowfish
Peaceful (1/10)
Temperature
✓ Compatible
Sulphur Crest Lithobates
24–28°C
Threadfin Rainbowfish
23–29°C
pH Range
✗ No overlap
Sulphur Crest Lithobates
7.8–8.6
Threadfin Rainbowfish
5.5–7.5
Hardness (dGH)
✓ Compatible
Sulphur Crest Lithobates
10–25
Threadfin Rainbowfish
1–12
Water Type
✓ Compatible
Sulphur Crest Lithobates
Freshwater Only
Threadfin Rainbowfish
Freshwater Only
Flow Preference
✓ Compatible
Sulphur Crest Lithobates
Moderate
Threadfin Rainbowfish
Low
Min Tank Volume
Combined: 250 L
Sulphur Crest Lithobates
250 L
Threadfin Rainbowfish
60 L
Swimming Level
Shared: 1 zone
Sulphur Crest Lithobates
MiddleBottom
Threadfin Rainbowfish
TopMiddle
🏷️Behavior Tags
Sulphur Crest Lithobates
Territorial (Defends specific area)Aggressive to same species/look-alikesFry Predator
Threadfin Rainbowfish
Nano / Bite-sized (Predation Risk)Shy / Slow Moving (Easily Stressed)Jumper (Lid Required)Hyperactive / Fast SwimmerAggressive Eater (Starves shy fish)
Stocking calculator

Can your tank handle Sulphur Crest Lithobates and Threadfin Rainbowfish?

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.

Sulphur Crest Lithobates
Threadfin Rainbowfish
Test both in my tank

Behaviour & Temperament

Sulphur Crest Lithobates is a moderately assertive species (6/10), while Threadfin Rainbowfish is peaceful (1/10). This notable difference means Sulphur Crest Lithobates may occasionally assert dominance over Threadfin Rainbowfish.

Sulphur Crest Lithobates and Threadfin Rainbowfish both frequent the Middle (Open Water) region of the setup. This overlap can increase competition for space, so providing ample room and cover is important to keep both species comfortable.

Worth noting: Threadfin Rainbowfish is a known jumper, so a tight-fitting lid is essential.

Water Parameters

The safe temperature window for both species falls between 24°C and 28°C. Aim for the midpoint of this range (around 26.0°C) for optimal comfort.

The pH requirements of Sulphur Crest Lithobates (7.8–8.6) and Threadfin Rainbowfish (5.5–7.5) do not overlap, making it impossible to satisfy both species simultaneously.

For general hardness, the shared comfort zone is 10–12 dGH. Regular testing will ensure conditions stay within this range.

Tank Setup

To house Sulphur Crest Lithobates and Threadfin Rainbowfish together, plan for an aquarium of at least 250 litres with a minimum length of 120 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), Plants - Densely covered, Plants - Floating. 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

Sulphur Crest Lithobates and Threadfin Rainbowfish 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 Sulphur Crest Lithobates and Threadfin Rainbowfish.

Show 1 more tank size

Frequently Asked Questions

Can Sulphur Crest Lithobates and Threadfin Rainbowfish live together?

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

What size tank do Sulphur Crest Lithobates and Threadfin Rainbowfish need?

A minimum of 250 litres (tank length at least 120 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 Sulphur Crest Lithobates and Threadfin Rainbowfish together?

Keep the aquarium between 24°C and 28°C. A target of around 26.0°C sits comfortably within both species' preferred ranges.

Are Sulphur Crest Lithobates or Threadfin Rainbowfish aggressive?

Sulphur Crest Lithobates is moderately assertive (6/10) and Threadfin Rainbowfish is peaceful (1/10). The gap in aggression levels means the calmer fish may experience stress from the more assertive one.

What pH do Sulphur Crest Lithobates and Threadfin Rainbowfish need?

Their pH requirements do not overlap. Sulphur Crest Lithobates prefers 7.8–8.6, while Threadfin Rainbowfish needs 5.5–7.5. This makes them incompatible in the same water chemistry.

How do I manage Sulphur Crest Lithobates's territorial behaviour?

Provide line-of-sight breaks using rocks, driftwood, and dense planting. A larger tank gives Sulphur Crest Lithobates 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 7, 2026
Last updated
May 7, 2026
Issues or corrections?
Contact the editorial team

Related Comparisons

Sulphur Crest Lithobates & Afra Cichlid

·

Possible with Caution
Sulphur Crest Lithobates: PeacefulAfra Cichlid: Peaceful

Sulphur Crest Lithobates & African Jewel Cichlid

·

Not Recommended
Sulphur Crest Lithobates: PeacefulAfrican Jewel Cichlid: Peaceful

Sulphur Crest Lithobates & Altolamprologus Calvus

·

Possible with Caution
Sulphur Crest Lithobates: PeacefulAltolamprologus Calvus: Peaceful

Sulphur Crest Lithobates & Altolamprologus Compressiceps

·

Possible with Caution
Sulphur Crest Lithobates: PeacefulAltolamprologus Compressiceps: Peaceful

Sulphur Crest Lithobates & Aurora Yellow Mbuna

·

Possible with Caution
Sulphur Crest Lithobates: PeacefulAurora Yellow Mbuna: Peaceful

Sulphur Crest Lithobates & Black Diamond Cichlid

·

Possible with Caution
Sulphur Crest Lithobates: PeacefulBlack Diamond Cichlid: Peaceful

Threadfin Rainbowfish & Honey Blue Eye

·

Possible with Caution
Threadfin Rainbowfish: PeacefulHoney Blue Eye: Peaceful

Threadfin Rainbowfish & Kabia rainbowfish

·

Possible with Caution
Threadfin Rainbowfish: Peaceful Kabia rainbowfish: Peaceful

Threadfin Rainbowfish & Kiunga Blue Eye

·

Possible with Caution
Threadfin Rainbowfish: PeacefulKiunga Blue Eye: Peaceful

Threadfin Rainbowfish & Lorentz's Rainbowfish

·

Possible with Caution
Threadfin Rainbowfish: PeacefulLorentz's Rainbowfish: Peaceful

Threadfin Rainbowfish & Mamberamo Rainbowfish

·

Possible with Caution
Threadfin Rainbowfish: PeacefulMamberamo Rainbowfish: Peaceful

Threadfin Rainbowfish & Ornate Rainbowfish

·

Possible with Caution
Threadfin Rainbowfish: PeacefulOrnate Rainbowfish: Peaceful