Species profile
Marginatus Pencilfish
Nannostomus marginatusMarginatus Pencilfish (Nannostomus marginatus) is a schooling community species for a cycled 10+ gallon freshwater aquarium. Plan for about 1.2 inches as an adult, 75-82°F water, pH 5-7, and moderate care. Keep a group of at least 6; larger groups often behave more naturally when the tank has room.
Community leaningModerate care
10 galMinimum tank
1.2 inAdult size
6Schooling minimum
75-82°FTemperature
Water Range
- pH
- 5-7
- GH
- 1-8 dGH
- KH
- 0-5 dKH
Behavior
- Temperament
- Peaceful
- Fin nipping
- 0/5
- Territory
- 0/5
Diet and Care
- Diet
- omnivore/micro-predator
- Diet difficulty
- 3/5
- Care difficulty
- 3/5
Planning Notes
Moderate care needs; may require mature grazing surfaces or supplemental fresh/frozen foods.
This species may need live, frozen, fresh, or otherwise specialized foods.
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