Can Rosy Red Minnow / Fathead Minnow and White Saum (Green Terror) Live Together?

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

Keeping Rosy Red Minnow / Fathead Minnow and White Saum (Green Terror) together is possible but requires caution due to differing aggression levels. Provide a spacious tank of at least 280 litres with plenty of hiding spots to reduce stress. Monitor behaviour closely, especially during the first few weeks.


At a Glance

Rosy Red Minnow / Fathead Minnow

Pimephales promelas

White Saum (Green Terror)

Andinoacara stalsbergi

🐠Family Group
Rosy Red Minnow / Fathead Minnow
Cyprinids
White Saum (Green Terror)
Cichlids - South American
Temperament
Rosy Red Minnow / Fathead Minnow
Peaceful (1/10)
White Saum (Green Terror)
Aggressive (8/10)
Temperature
✓ Compatible
Rosy Red Minnow / Fathead Minnow
10–24°C
White Saum (Green Terror)
20–25°C
pH Range
✓ Compatible
Rosy Red Minnow / Fathead Minnow
6.5–8
White Saum (Green Terror)
6.5–8
Hardness (dGH)
✓ Compatible
Rosy Red Minnow / Fathead Minnow
4–20
White Saum (Green Terror)
5–20
Water Type
✓ Compatible
Rosy Red Minnow / Fathead Minnow
Freshwater Only
White Saum (Green Terror)
Freshwater Only
Flow Preference
✓ Compatible
Rosy Red Minnow / Fathead Minnow
Moderate
White Saum (Green Terror)
Moderate
Min Tank Volume
Combined: 280 L
Rosy Red Minnow / Fathead Minnow
75 L
White Saum (Green Terror)
280 L
Swimming Level
Shared: 1 zone
Rosy Red Minnow / Fathead Minnow
TopMiddle
White Saum (Green Terror)
MiddleBottom
🏷️Behavior Tags
Rosy Red Minnow / Fathead Minnow
Hyperactive / Fast Swimmer
White Saum (Green Terror)
Generally AggressiveTerritorial (Defends specific area)Digger (Disturbs Substrate)Plant DestroyerPiscivore (Eats small/nano fish)Shrimp EaterFry Predator
Stocking calculator

Can your tank handle Rosy Red Minnow / Fathead Minnow and White Saum (Green Terror)?

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.

Rosy Red Minnow / Fathead Minnow
White Saum (Green Terror)
Test both in my tank

Behaviour & Temperament

Rosy Red Minnow / Fathead Minnow is a peaceful species (1/10), while White Saum (Green Terror) is semi-aggressive (8/10). This notable difference means White Saum (Green Terror) may occasionally assert dominance over Rosy Red Minnow / Fathead Minnow.

Large aggression gap (7 points) between Rosy Red Minnow / Fathead Minnow and White Saum (Green Terror) increases stress risk for the more peaceful fish.

Rosy Red Minnow / Fathead Minnow and White Saum (Green Terror) 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.

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 Rosy Red Minnow / Fathead Minnow and White Saum (Green Terror) to establish separate territories. Add plenty of line-of-sight breaks using driftwood, rocks, and dense planting to reduce territorial confrontations. A larger aquarium with ample hiding spots can help diffuse aggression and give the less dominant fish space to retreat.

Water Parameters

The safe temperature window for both species falls between 20°C and 24°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 5–20 dGH. Regular testing will ensure conditions stay within this range.

Tank Setup

To house Rosy Red Minnow / Fathead Minnow and White Saum (Green Terror) together, plan for an aquarium of at least 280 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: Smooth Gravel (Sensitive Barbels), Sand (Sifters), Driftwood (Digestion/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 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. Rosy Red Minnow / Fathead Minnow and White Saum (Green Terror) 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 Rosy Red Minnow / Fathead Minnow and White Saum (Green Terror).

Show 1 more tank size

Frequently Asked Questions

Can Rosy Red Minnow / Fathead Minnow and White Saum (Green Terror) live together?

They can coexist, but the pairing requires careful monitoring. Provide ample space (at least 280 litres), plenty of hiding spots, and watch for signs of stress or aggression.

What size tank do Rosy Red Minnow / Fathead Minnow and White Saum (Green Terror) need?

A minimum of 280 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 Rosy Red Minnow / Fathead Minnow and White Saum (Green Terror) together?

Keep the aquarium between 20°C and 24°C. A target of around 22.0°C sits comfortably within both species' preferred ranges.

Are Rosy Red Minnow / Fathead Minnow or White Saum (Green Terror) aggressive?

Rosy Red Minnow / Fathead Minnow is peaceful (1/10) and White Saum (Green Terror) is semi-aggressive (8/10). The gap in aggression levels means the calmer fish may experience stress from the more assertive one.

What pH do Rosy Red Minnow / Fathead Minnow and White Saum (Green Terror) 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.

How do I manage White Saum (Green Terror)'s territorial behaviour?

Provide line-of-sight breaks using rocks, driftwood, and dense planting. A larger tank gives White Saum (Green Terror) 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
Issues or corrections?
Contact the editorial team

Related Comparisons

Rosy Red Minnow / Fathead Minnow & Blackline Rasbora

·

Ideal Tank Mates
Rosy Red Minnow / Fathead Minnow: PeacefulBlackline Rasbora: Peaceful

Rosy Red Minnow / Fathead Minnow & Copper Harlequin Rasbora

·

Possible with Caution
Rosy Red Minnow / Fathead Minnow: PeacefulCopper Harlequin Rasbora: Peaceful

Rosy Red Minnow / Fathead Minnow & Glowlight Danio

·

Ideal Tank Mates
Rosy Red Minnow / Fathead Minnow: PeacefulGlowlight Danio: Peaceful

Rosy Red Minnow / Fathead Minnow & Harlequin Rasbora

·

Ideal Tank Mates
Rosy Red Minnow / Fathead Minnow: PeacefulHarlequin Rasbora: Peaceful

Rosy Red Minnow / Fathead Minnow & Neon Green Rasbora (Kubotai)

·

Ideal Tank Mates
Rosy Red Minnow / Fathead Minnow: PeacefulNeon Green Rasbora (Kubotai): Peaceful

Rosy Red Minnow / Fathead Minnow & Pearl Danio

·

Ideal Tank Mates
Rosy Red Minnow / Fathead Minnow: PeacefulPearl Danio: Peaceful

White Saum (Green Terror) & Andinoacara sp. Gold Saum

·

Possible with Caution
White Saum (Green Terror): PeacefulAndinoacara sp. Gold Saum: Peaceful

White Saum (Green Terror) & Blue Acara

·

Possible with Caution
White Saum (Green Terror): PeacefulBlue Acara: Peaceful

White Saum (Green Terror) & Green Terror

·

Possible with Caution
White Saum (Green Terror): PeacefulGreen Terror: Peaceful

White Saum (Green Terror) & Oscar

·

Possible with Caution
White Saum (Green Terror): PeacefulOscar: Peaceful

White Saum (Green Terror) & Platinum Acara

·

Possible with Caution
White Saum (Green Terror): PeacefulPlatinum Acara: Peaceful

White Saum (Green Terror) & Red Terror (Festa's Cichlid)

·

Possible with Caution
White Saum (Green Terror): PeacefulRed Terror (Festa's Cichlid): Peaceful