Diamond Tetras 3–3.5cm (Moenkhausia pittieri) are often considered the “jewel” of their genus. As they grow, their silvery‑violet body develops a beautiful green and gold or orange iridescent sheen, giving them a glittering, diamond‑like appearance under aquarium lighting.
At the 3–3.5cm size, these fish are juveniles, so you’re getting young Diamond Tetras 3–3.5cm that will continue to colour up and become even more impressive as they reach adulthood.
Appearance & Behaviour of Diamond Tetras 3–3.5cm
- Slender, laterally compressed body with silvery‑violet scales
- Green, gold and orange iridescence that intensifies as they mature
- Long, flowing fins in adults, especially males
- Active, mid‑water schooling fish that are almost always on the move
Diamond Tetras 3–3.5cm are peaceful and make excellent community fish, provided they are kept in a proper group and with suitable tank mates.
Tank Requirements for Diamond Tetras 3–3.5cm
To keep Diamond Tetras 3–3.5cm happy and healthy:
- Tank size: From around 60L+ for a small group, larger is always better
- Water: Prefer soft, slightly acidic water; they do not do well in very hard water
- Filtration: Gentle, reliable filtration with good oxygenation
- Décor:
- Well‑planted tank with background and mid‑ground plants
- Darker substrate to show off their colours
- Floating plants or subdued lighting to mimic their natural habitat
They appreciate peat‑filtered or tannin‑rich water and softer conditions, which help bring out their best colour and natural behaviour.
Community Compatibility
Diamond Tetras 3–3.5cm are:
- Peaceful, ideal for community tanks with other non‑aggressive species
- Best kept in a school of at least 6, with 8–10+ being even better
- Active feeders – if underfed, they may start to nibble on softer aquarium plants
Good tank mates include:
- Other peaceful tetras and rasboras
- Corydoras and small, peaceful catfish
- Dwarf cichlids, gouramis and similar calm species
- Shrimp and snails may be possible, though tiny shrimplets can be at risk
As long as Diamond Tetras 3–3.5cm are kept well fed and in a proper group, they generally leave plants and tank mates alone.
Feeding Diamond Tetras 3–3.5cm
The diet for Diamond Tetras 3–3.5cm should be varied and high quality:
- Staple of high‑quality tropical flakes or micro pellets
- Regular offerings of frozen or live foods (e.g. daphnia, brine shrimp, bloodworms)
- Occasional finely chopped or micro foods for smaller individuals
Because they are active and “on the go” all day, Diamond Tetras 3–3.5cm have a healthy appetite. Feed small amounts 1–2 times daily, ensuring they consume everything within a few minutes to maintain good water quality.
Ideal for Planted & Soft Water Aquariums
If you’re running a planted, soft‑water community tank, Diamond Tetras 3–3.5cm are a fantastic choice:
- Their shimmering, diamond‑like scales look stunning against green plants and dark substrates
- A schooling group provides constant movement and interest in the mid‑water
- Their colours continue to improve as they mature, rewarding patient aquarists
Provide soft, slightly acidic water, plenty of plants and a good‑sized group, and Diamond Tetras 3–3.5cm will quickly become one of the standout species in your aquarium.