Neon Tetra Care Guide

Water Parameters

In the wild, neon tetras inhabit slow-moving, heavily shaded blackwater streams in the upper Amazon basin (Peru, Colombia, Brazil). The water is extremely soft, acidic (pH 4–5), dark with tannins, and cool. In the aquarium, they are more adaptable than wild conditions suggest — captive-bred neons tolerate pH up to 7.5 and moderate hardness — but they thrive in softer, slightly acidic conditions.

If your tap water is hard (above 15 dGH), consider blending with RO water to bring GH down to 5–8 dGH. Adding driftwood or Indian almond leaves naturally acidifies the water and releases tannins that neons love — you'll see brighter colours in soft, tannin-stained water.

Tank Size and Setup

Minimum tank: 40 litres (10 gallons) for a school of 6. But a 60–80 litre tank (15–20 gallons) is a far better choice — more water volume means more stable parameters, which directly reduces stress and disease in neon tetras.

Neon tetras are mid-water swimmers that love cover. The ideal setup includes:

• Dense planting — Java fern, Anubias, and floating plants to dim the light and provide refuge
• Dark substrate — dark sand or gravel makes their colours pop dramatically
• Driftwood — releases tannins, slightly acidifies water, provides shelter
• Low to moderate flow — they come from slow-moving water; strong flow stresses them
• Subdued lighting — bright open tanks make neons hide; floating plants or a dimmer dramatically improves their behaviour

Tank Mates

Neon tetras are small (3–4 cm), peaceful, and mid-water fish. Choose tank mates that are similarly sized, non-aggressive, and comfortable with soft, slightly acidic conditions.

Feeding

Neon tetras are omnivores with small mouths — they need micro-sized food. In the wild they eat tiny invertebrates, insect larvae, algae, and plant matter.

• Micro pellets or nano flakes — the staple. Ensure the particle size is small enough for their tiny mouths (1–1.5 mm max)
• Frozen or live micro foods — baby brine shrimp, micro worms, daphnia, and bloodworms greatly improve colour and condition
• Blanched vegetables — occasionally offer blanched spinach or zucchini for added fibre

Feed once or twice daily, only what they can eat in 2–3 minutes. Overfeeding is a primary cause of poor water quality in neon tetra tanks. Remove any uneaten food promptly.

Schooling Behaviour

This cannot be overstated: neon tetras must be kept in a school. They are shoaling fish that have evolved to find safety in numbers. A lone neon tetra or a group of fewer than 6 will be chronically stressed — you'll see pale colours, hiding, and erratic swimming near the surface.

A school of 10–15 neon tetras shows dramatically different behaviour: coordinated shoaling, bold mid-water swimming, brilliant colours, and natural spawning attempts. Bigger schools are always better as long as your tank and filtration can support them.

Common Diseases

Breeding

Breeding neon tetras in a home aquarium is possible but challenging — it requires a dedicated breeding tank with very specific conditions:

• Dedicated 20–40 L breeding tank — very dim light, dark sides
• Very soft, acidic water — pH 5.5–6.0, GH under 2 dGH (RO water or rainwater)
• Temperature: 22–24 °C (cooler than the main tank to trigger spawning)
• Fine-leaved plants or spawning mop — Java moss works well
• Remove adults after spawning — neons eat their own eggs
• Eggs hatch in 24–30 hours; fry are free-swimming after 3–4 days
• First foods: infusoria, then baby brine shrimp as they grow

The main challenge is sourcing soft enough water. Most tap water is far too hard for neon tetra eggs to survive. Using 100% RO water with a small amount of peat-filtered water is the standard approach among breeders.

Frequently Asked Questions

What size tank do neon tetras need?

Neon tetras need a minimum 40-litre (10-gallon) tank to keep a school of 6. A 60–80 litre tank is better as it provides more swimming room and greater water stability. They are schooling fish and must never be kept alone or in groups of fewer than 6.

What water temperature do neon tetras need?

Neon tetras thrive at 22–26 °C (72–79 °F). They originate from cool blackwater streams in the Amazon basin and do not tolerate temperatures above 28 °C well. Aim for a stable 24–25 °C for most community setups.

Can neon tetras live with betta fish?

Sometimes, but with caution. Some betta fish tolerate neon tetras peacefully; others will nip at or eat them. If you try this combination, use a tank of at least 60 litres, provide plenty of plants and hiding spots, and monitor closely. Never add neon tetras to a tank with a betta that has shown aggression.

What is neon tetra disease?

Neon Tetra Disease (NTD) is caused by a microsporidian parasite (Pleistophora hyphessobryconis). It causes colour fading starting from the mid-body, a curved spine, and white cysts under the skin. There is no effective treatment — infected fish should be removed immediately to prevent spread. It enters tanks through infected live food or unquarantined new fish.

How many neon tetras should be kept together?

Neon tetras are schooling fish and must be kept in groups of at least 6. A school of 10–15 shows much more natural behaviour, bolder colours, and less stress. Keeping fewer than 6 causes chronic stress, pale colours, and excessive hiding.