Peaceful Community (Tetras, Rasboras, Corydoras)
The safest, most widely compatible mix -- small, peaceful schooling fish and bottom-dwellers that generally get along.
Runner-up: Semi-Aggressive Community · Retake the quiz
Why this fits you
- You want the lowest-risk, most broadly compatible stocking approach.
- Small, peaceful schooling fish and calm bottom-dwellers appeal to you.
- You're newer to stocking and want to minimize aggression risk.
A peaceful community built around small schooling fish (tetras, rasboras) and calm bottom-dwellers (corydoras catfish) is the lowest-risk stocking approach -- these species are broadly compatible with each other and rarely show serious aggression, making this the standard recommendation for most community tanks.
How it compares
| Approach | Risk level | Examples |
| Peaceful Community | Lowest | Tetras, rasboras, corydoras |
| Semi-Aggressive Community | Moderate | Barbs, larger tetras, gouramis |
| Species-Only Tank | Varies, often high if mismatched | Certain cichlids, bettas |
Buying checklist
- Keep schooling species in appropriate group sizes (usually 6+) -- too few can cause stress and odd behavior
- Research each specific species' adult size and temperament before adding, even within this generally peaceful category
- Corydoras and most tetras/rasboras share similar water parameter needs, which helps
When this isn’t the right fit
A peaceful community is not right if you want large, active or territorial fish. Even peaceful species need the right group size, compatible water and enough space, and fin nipping and bullying can still appear. Check each species instead of trusting the label.
Other results from this quiz may suit your situation better:
- Species-Only Tank (Single Species or Territorial Fish): for fish that don't play well with others
- Semi-Aggressive Community (Barbs, Larger Tetras, Gouramis): for a bit more personality and activity
If your fish or plants show signs of stress or illness, test your water and ask an experienced fishkeeper or an aquatic veterinarian before you treat.
Run the numbers
Frequently asked questions
How many tetras should I keep together?
Most schooling tetras do best in groups of 6 or more -- too few can lead to stress, fin-nipping, and unnatural behavior even among normally peaceful species.
Can I mix different tetra species in the same school?
They'll generally coexist peacefully, but each species won't necessarily school together as one group -- for true schooling behavior, keep adequate numbers of each individual species.
Are corydoras compatible with most community fish?
Yes, generally -- corydoras are peaceful bottom-dwellers that coexist well with most small, non-aggressive community fish sharing similar water parameters.
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