Can Brown Hoplo Catfish and Florida Flagfish Live Together?

Reviewed by Guidarium Editorial DeskUpdated May 6, 2026
Possible with Caution

Keeping Brown Hoplo Catfish and Florida Flagfish together is possible but requires caution, though some care is needed. Provide a spacious tank of at least 200 litres with plenty of hiding spots to reduce stress. Monitor behaviour closely, especially during the first few weeks.


At a Glance

Brown Hoplo Catfish

Hoplosternum littorale

Florida Flagfish

Jordanella floridae

🐠Family Group
Brown Hoplo Catfish
Catfish
Florida Flagfish
Killifish
Temperament
Brown Hoplo Catfish
Peaceful (2/10)
Florida Flagfish
Semi-Aggressive (5/10)
Temperature
✓ Compatible
Brown Hoplo Catfish
18–28°C
Florida Flagfish
18–26°C
pH Range
✓ Compatible
Brown Hoplo Catfish
6–8
Florida Flagfish
6.5–8.5
Hardness (dGH)
✓ Compatible
Brown Hoplo Catfish
4–20
Florida Flagfish
10–25
Water Type
✓ Compatible
Brown Hoplo Catfish
Freshwater Only
Florida Flagfish
Brackish Tolerant
Flow Preference
✓ Compatible
Brown Hoplo Catfish
Low
Florida Flagfish
Low
Min Tank Volume
Combined: 200 L
Brown Hoplo Catfish
200 L
Florida Flagfish
75 L
Swimming Level
Shared: 2 zones
Brown Hoplo Catfish
BottomMiddle
Florida Flagfish
MiddleBottom
🏷️Behavior Tags
Brown Hoplo Catfish
Hyperactive / Fast SwimmerDigger (Disturbs Substrate)Plant DestroyerFry PredatorJumper (Lid Required)
Florida Flagfish
Fin NipperAggressive to same species/look-alikesHyperactive / Fast SwimmerTerritorial (Defends specific area)
Stocking calculator

Can your tank handle Brown Hoplo Catfish and Florida Flagfish?

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.

Brown Hoplo Catfish
Florida Flagfish
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Behaviour & Temperament

Brown Hoplo Catfish is a peaceful species (2/10), while Florida Flagfish is moderately assertive (5/10). This modest difference means Florida Flagfish may occasionally assert dominance over Brown Hoplo Catfish.

Brown Hoplo Catfish and Florida Flagfish both frequent the Bottom (Substrate) and 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: Brown Hoplo Catfish is a known jumper, so a tight-fitting lid is essential.

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 Brown Hoplo Catfish and Florida Flagfish 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 18°C and 26°C. Aim for the midpoint of this range (around 22.0°C) for optimal comfort.

Both fish can tolerate a pH between 6.5 and 8. Maintaining a stable value within this band is more important than hitting an exact number.

For general hardness, the shared comfort zone is 10–20 dGH. Regular testing will ensure conditions stay within this range.

Tank Setup

To house Brown Hoplo Catfish and Florida Flagfish together, plan for an aquarium of at least 200 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.

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

Note a potential conflict in setup requirements: Brown Hoplo Catfish is a plant destroyer, which conflicts with Florida Flagfish's requirement for live plants. Compromise where possible or prioritise the more critical need.

Both species do well with low (still water) 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. Brown Hoplo Catfish and Florida Flagfish 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 Brown Hoplo Catfish and Florida Flagfish.

Show 5 more tank sizes

Frequently Asked Questions

Can Brown Hoplo Catfish and Florida Flagfish live together?

They can coexist, but the pairing requires careful monitoring. Provide ample space (at least 200 litres), plenty of hiding spots, and watch for signs of stress or aggression.

What size tank do Brown Hoplo Catfish and Florida Flagfish need?

A minimum of 200 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 Brown Hoplo Catfish and Florida Flagfish together?

Keep the aquarium between 18°C and 26°C. A target of around 22.0°C sits comfortably within both species' preferred ranges.

Are Brown Hoplo Catfish or Florida Flagfish aggressive?

Brown Hoplo Catfish is peaceful (2/10) and Florida Flagfish is moderately assertive (5/10). Their similar temperaments generally lead to a peaceful coexistence.

What pH do Brown Hoplo Catfish and Florida Flagfish need?

Both species overlap in the 6.5–8 pH range. Consistency is key — avoid sudden swings, and test regularly to stay within this window.

Will Florida Flagfish nip Brown Hoplo Catfish's fins?

Florida Flagfish is a known fin nipper. If Brown Hoplo Catfish has long or flowing fins, there is a real risk of fin damage. Keeping Florida Flagfish in a larger group can help redirect nipping behaviour toward conspecifics.

How do I manage Florida Flagfish's territorial behaviour?

Provide line-of-sight breaks using rocks, driftwood, and dense planting. A larger tank gives Florida Flagfish 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?
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