Can Knight Goby and Thinbar Datnoid Live Together?

Reviewed by Guidarium Editorial DeskUpdated May 11, 2026
Possible with Caution

Keeping Knight Goby and Thinbar Datnoid together is possible but requires caution due to potential behavioral clashes. Provide a spacious tank of at least 570 litres with plenty of hiding spots to reduce stress. Monitor behaviour closely, especially during the first few weeks.


At a Glance

Knight Goby

Stigmatogobius sadanundio

Thinbar Datnoid

Datnioides undecimradiatus

🐠Family Group
Knight Goby
Gobies & Gudgeons
Thinbar Datnoid
Oddballs
Temperament
Knight Goby
Semi-Aggressive (6/10)
Thinbar Datnoid
Semi-Aggressive (6/10)
Temperature
✓ Compatible
Knight Goby
20–28°C
Thinbar Datnoid
24–28°C
pH Range
✓ Compatible
Knight Goby
7–8.5
Thinbar Datnoid
6.5–7.5
Hardness (dGH)
✓ Compatible
Knight Goby
10–30
Thinbar Datnoid
5–18
Water Type
✓ Compatible
Knight Goby
Brackish Tolerant
Thinbar Datnoid
Brackish Tolerant
Flow Preference
✓ Compatible
Knight Goby
Moderate
Thinbar Datnoid
Moderate
Min Tank Volume
Combined: 570 L
Knight Goby
75 L
Thinbar Datnoid
570 L
Swimming Level
Shared: 2 zones
Knight Goby
MiddleBottom
Thinbar Datnoid
MiddleBottom
🏷️Behavior Tags
Knight Goby
Fin NipperShrimp EaterFry PredatorTerritorial (Defends specific area)Digger (Disturbs Substrate)Aggressive to same species/look-alikes
Thinbar Datnoid
Piscivore (Eats small/nano fish)Shrimp EaterFry PredatorShy / Slow Moving (Easily Stressed)Territorial (Defends specific area)Aggressive to same species/look-alikes
Stocking calculator

Can your tank handle Knight Goby and Thinbar Datnoid?

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.

Knight Goby
Thinbar Datnoid
Test both in my tank

Behaviour & Temperament

Both Knight Goby and Thinbar Datnoid are moderately assertive species with an aggression score of 6/10. Their matching temperaments mean neither fish is likely to dominate the other in a shared aquarium.

Knight Goby and Thinbar Datnoid both frequent the Middle (Open Water) and 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.

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 Knight Goby and Thinbar Datnoid to establish separate territories. Add plenty of line-of-sight breaks using driftwood, rocks, and dense planting to reduce territorial confrontations. Keep fin nippers in larger groups to distribute nipping behaviour among conspecifics rather than tank mates.

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.

Both fish can tolerate a pH between 7 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 10–18 dGH. Regular testing will ensure conditions stay within this range.

Tank Setup

To house Knight Goby and Thinbar Datnoid together, plan for an aquarium of at least 570 litres with a minimum length of 150 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: Sand (Sifters), Shells (Breeding/Hiding), Driftwood (Digestion/Hiding), 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 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. Knight Goby and Thinbar Datnoid 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 Knight Goby and Thinbar Datnoid.

Frequently Asked Questions

Can Knight Goby and Thinbar Datnoid live together?

They can coexist, but the pairing requires careful monitoring. Provide ample space (at least 570 litres), plenty of hiding spots, and watch for signs of stress or aggression.

What size tank do Knight Goby and Thinbar Datnoid need?

A minimum of 570 litres (tank length at least 150 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 Knight Goby and Thinbar Datnoid 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 Knight Goby or Thinbar Datnoid aggressive?

Knight Goby is moderately assertive (6/10) and Thinbar Datnoid is moderately assertive (6/10). Their similar temperaments generally lead to a peaceful coexistence.

What pH do Knight Goby and Thinbar Datnoid need?

Both species overlap in the 7–7.5 pH range. Consistency is key — avoid sudden swings, and test regularly to stay within this window.

Will Knight Goby nip Thinbar Datnoid's fins?

Knight Goby is a known fin nipper. If Thinbar Datnoid has long or flowing fins, there is a real risk of fin damage. Keeping Knight Goby in a larger group can help redirect nipping behaviour toward conspecifics.

How do I manage Knight Goby's territorial behaviour?

Provide line-of-sight breaks using rocks, driftwood, and dense planting. A larger tank gives Knight Goby 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 11, 2026
Last updated
May 11, 2026
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