Neon Tetra vs Cardinal Tetra

The same axes for both animals, taken from the same care guides, so this is a like-for-like comparison rather than two articles written months apart. Neither animal is the right answer on its own — the question is which one fits the space, the budget and the routine you actually have.

Freshwater Fish

Neon Tetra

Paracheirodon innesi

Difficulty

Intermediate

Lifespan

5-8 years

Adult size

3-4cm / 1.2-1.5in

Minimum space

57 L (15 US gal)

Company

Must be kept in at least 8

Daily time

10-15 min daily; weekly water change

Running cost

Low

Habitat

Aquarium 57L+ / 15gal+, heated and filtered

Diet

Omnivore (micro-flake, small pellet, live foods)

Suits you if

Established, mature planted aquariums. Peaceful community tanks of small species. Keepers wanting a schooling display

Watch out for

Adding to brand-new, uncycled tanks. Keeping too few and stressing the school. Neon tetra disease spreading without quarantine

Full Neon Tetra guide

Freshwater Fish

Cardinal Tetra

Paracheirodon axelrodi

Difficulty

Intermediate

Lifespan

4-6 years

Adult size

4-5 cm / 1.5-2 in

Minimum space

75 L (20 US gal)

Company

Must be kept in at least 10

Daily time

Low-moderate; daily feeding, weekly water change

Running cost

Low-Medium

Habitat

Aquarium 75L+ / 20gal+, heated and filtered

Diet

Omnivore; micro pellets, flakes, frozen foods

Suits you if

Planted soft-water community aquariums. Keepers wanting a colourful display shoal. Those with a mature, stable cycled tank

Watch out for

Adding fragile wild imports to immature tanks. Keeping too few, causing chronic stress. Hard, alkaline water dulling colour and health

Full Cardinal Tetra guide

How to read this

Every row is filled from the same field of the same care guide for both animals, so nothing here is cherry-picked to favour one of them.

Minimum space is the figure from each species' housing guidance, converted to one unit. It is a floor, not a target.

What this does not tell you: your experience, your household, your climate, or which animal you will actually enjoy. Difficulty is our judgement, not a measurement. Read both full guides before deciding — and if the honest answer is neither, that is a good outcome too.