Can Plain Silver Dollar and Sunset Hap Live Together?

Reviewed by Guidarium Editorial DeskUpdated May 4, 2026
Not Recommended

Plain Silver Dollar and Sunset Hap 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

Plain Silver Dollar

Metynnis hypsauchen

Sunset Hap

Dimidiochromis strigatus

🐠Family Group
Plain Silver Dollar
Characins
Sunset Hap
Cichlids - African
Temperament
Plain Silver Dollar
Peaceful (2/10)
Sunset Hap
Semi-Aggressive (6/10)
Temperature
✓ Compatible
Plain Silver Dollar
24–28°C
Sunset Hap
24–28°C
pH Range
✗ No overlap
Plain Silver Dollar
6–7.5
Sunset Hap
7.6–8.6
Hardness (dGH)
✓ Compatible
Plain Silver Dollar
4–15
Sunset Hap
10–25
Water Type
✓ Compatible
Plain Silver Dollar
Freshwater Only
Sunset Hap
Freshwater Only
Flow Preference
✓ Compatible
Plain Silver Dollar
Moderate
Sunset Hap
Moderate
Min Tank Volume
Combined: 400 L
Plain Silver Dollar
280 L
Sunset Hap
400 L
Swimming Level
Shared: 1 zone
Plain Silver Dollar
MiddleTop
Sunset Hap
MiddleBottom
🏷️Behavior Tags
Plain Silver Dollar
Hyperactive / Fast SwimmerPlant DestroyerJumper (Lid Required)Shy / Slow Moving (Easily Stressed)
Sunset Hap
Piscivore (Eats small/nano fish)Aggressive to same species/look-alikesHyperactive / Fast SwimmerTerritorial (Defends specific area)
Stocking calculator

Can your tank handle Plain Silver Dollar and Sunset Hap?

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.

Plain Silver Dollar
Sunset Hap
Test both in my tank

Behaviour & Temperament

Plain Silver Dollar is a peaceful species (2/10), while Sunset Hap is moderately assertive (6/10). This notable difference means Sunset Hap may occasionally assert dominance over Plain Silver Dollar.

Plain Silver Dollar and Sunset Hap 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.

Additional behavioural considerations to keep in mind: Hyperactive swimmers can stress shy, slow-moving species through constant motion.

Worth noting: Plain Silver Dollar 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 Plain Silver Dollar (6–7.5) and Sunset Hap (7.6–8.6) 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 Plain Silver Dollar and Sunset Hap together, plan for an aquarium of at least 400 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.

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: Smooth Gravel (Sensitive Barbels), Driftwood (Digestion/Hiding), Sand (Sifters). 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

Plain Silver Dollar and Sunset Hap 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 Plain Silver Dollar and Sunset Hap.

Frequently Asked Questions

Can Plain Silver Dollar and Sunset Hap live together?

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

What size tank do Plain Silver Dollar and Sunset Hap need?

A minimum of 400 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 Plain Silver Dollar and Sunset Hap 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 Plain Silver Dollar or Sunset Hap aggressive?

Plain Silver Dollar is peaceful (2/10) and Sunset Hap is moderately assertive (6/10). The gap in aggression levels means the calmer fish may experience stress from the more assertive one.

What pH do Plain Silver Dollar and Sunset Hap need?

Their pH requirements do not overlap. Plain Silver Dollar prefers 6–7.5, while Sunset Hap needs 7.6–8.6. This makes them incompatible in the same water chemistry.

How do I manage Sunset Hap's territorial behaviour?

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