Green Neon

Green Neon Tetras are beautiful, peaceful freshwater fish known for their brilliant iridescent blue-green stripe that runs along the length of their body. Their shimmering colour changes depending on the aquarium lighting, creating a stunning display of turquoise, blue and green.

Although similar in appearance to the common Neon Tetra, Green Neons are smaller and have a more prominent blue-green stripe with very little red colouring.

These tiny, active schooling fish are a fantastic addition to mature, planted tropical aquariums. When kept in a good-sized group, their shimmering colours and natural schooling behaviour create a beautiful display of movement throughout the tank.

Scientific Name: Paracheirodon simulans

Care Level: Moderate

Temperament: Peaceful, active and social

Maximum Size: Approximately 2–2.5 cm

Lifespan: Approximately 3–5 years with proper care

Minimum Tank Size:

A minimum of 40 litres is recommended for a small group of Green Neon Tetras, although a 60-litre aquarium or larger is preferred for improved water stability and additional swimming space.

Despite their small size, Green Neons are active schooling fish that appreciate plenty of room to swim together.

A well-planted aquarium with driftwood, darker substrates, shaded areas and some open swimming space provides an ideal environment.

Floating plants and gentle lighting can help recreate their natural habitat and encourage their beautiful colours to stand out.

How Many Should Be Kept Together?

Green Neon Tetras should be kept in groups of at least 8–10, with larger groups encouraged when aquarium space allows.

These fish are naturally social and feel much more secure when surrounded by others of their own species.

Keeping them individually or in small numbers can cause stress, shyness and reduced natural schooling behaviour.

A group of 10–15 Green Neons can create a particularly beautiful display in a suitably sized planted aquarium.

Ideal Water Temperature:

24–27°C, with approximately 25–26°C being an excellent target for everyday care.

Green Neon Tetras prefer warm, stable tropical temperatures and require a reliable aquarium heater.

Water Conditions:

Green Neon Tetras naturally inhabit soft, acidic blackwater environments and generally do best when similar conditions are provided in the aquarium.

• Ideal pH: Approximately 4.5–6.5

• Water Hardness: Soft, ideally 1–8 dGH

• Water Flow: Gentle to moderate

• Ammonia and Nitrite: 0 ppm

• Aquarium: Fully cycled, mature and well maintained

Although some captive populations may adapt to water closer to neutral, consistently hard or alkaline water is not ideal for this species.

They are sensitive to sudden changes in water parameters, making stable conditions and regular aquarium maintenance especially important.

Diet:

Green Neon Tetras are omnivores and require a varied diet of small, appropriately sized foods.

Quality micro pellets or finely crushed tropical flakes can form the foundation of their diet, supplemented with occasional frozen or live foods such as baby brine shrimp, daphnia and cyclops.

Due to their tiny mouths, it is important to ensure food particles are small enough for them to eat comfortably.

Feed small portions and avoid overfeeding to maintain good water quality.

Compatibility:

Green Neon Tetras are peaceful fish best suited to carefully planned community aquariums with other small, non-aggressive species that enjoy similar water conditions.

Suitable tank mates may include:

• Ember Tetras

• Other small, peaceful Tetras with compatible water requirements

• Small Rasboras suited to soft, acidic water

• Pygmy Corydoras

• Otocinclus in mature, suitable aquariums

• Peaceful freshwater shrimp, although very small shrimp babies may be eaten

Avoid housing Green Neon Tetras with large, aggressive or predatory fish.

Due to their very small size, even some generally peaceful larger fish may view them as food.

Things to Be Cautious Of:

• Water Quality: Green Neon Tetras are sensitive to poor or unstable water conditions and should only be introduced to fully cycled, established aquariums.

• Group Size: They should be kept in groups of at least 8–10 to encourage natural behaviour and reduce stress.

• Small Size: Their tiny bodies make them vulnerable to larger fish, even those that are not normally considered aggressive.

• Water Hardness: They naturally prefer soft, acidic conditions and may not thrive in hard, alkaline aquariums.

• Sudden Changes: Rapid changes in temperature, pH or water chemistry can cause significant stress.

• Feeding: Their small mouths require suitably sized foods, and they may struggle to compete with larger or faster-feeding fish.

• New Aquariums: They are not recommended as starter fish for newly established aquariums.

Helpful Notes:

Green Neon Tetras are a wonderful choice for aquarists wanting a smaller, more delicate alternative to the traditional Neon Tetra.

Their brilliant blue-green stripe is particularly striking against dark substrates, driftwood and lush green aquatic plants.

They naturally inhabit shaded waterways, so providing areas of subdued lighting and plant cover will help them feel secure and encourage their natural behaviour.

Although small and peaceful, Green Neon Tetras require more attention to water conditions than some other common aquarium fish. They are best suited to aquarists who can provide a mature aquarium with stable, soft water.