Neon Tetra vs Cardinal Tetra
Edited by Ivan F.
Short answer
They need the same tank and group size, so choose by temperature. Neon tetras suit a cooler tank, and cardinal tetras suit a warmer one. Cardinals are often wild-caught, and neons have long been mass-bred, so buy either one with care. Our rules rate them a good match if you want both.
Side by side
Figures come from our species pages, which list their sources.
| Measure | Neon Tetra | Cardinal Tetra |
|---|---|---|
| Adult size | 1.2 in (3 cm) | 1.4 in (3.5 cm) |
| Minimum tank | 14 US gal (54 L) | 14 US gal (54 L) |
| Minimum group | 8 | 8 |
| Temperature | 70–77°F (21–25°C) | 73–84°F (23–29°C) |
| pH | 4–7.5 | 3.5–7.5 |
| Hardness | 1–12 dGH | 1–12 dGH |
| Care level | Easy | Easy |
| Lifespan | 3–5 years | 4–5 years |
| Temperament | Peaceful | Peaceful |
| Swim zone | Mid-Water | Mid-Water |
What the figures do not show
How to tell them apart
Seriously Fish says a cardinal has relatively more red on its body than a neon, and a broader blue stripe that runs further toward the tail.
Where they come from
Seriously Fish says cardinals are now bred on a large scale, yet many sold are still wild-caught, and that wild fish tolerate worsening water less well.
Breeding quality
Seriously Fish says years of commercial breeding have weakened the ornamental neon strain, and that defects and ill-health are widespread, so choose stock carefully.
Disease to know
Seriously Fish warns that neons are susceptible to neon tetra disease, which it calls virtually untreatable once advanced.
Which to choose
Choose Neon Tetra if
- Your tank runs toward the cooler end of the tropical range.
- Your other fish prefer cooler water.
Choose Cardinal Tetra if
- Your tank runs warm, or your other fish need warmer water.
- You want more red on the body.
This section is our advice, based on the figures and sources on this page.
Can they live together?
Good match
Temperature both accept: 73–77°F (23–25°C)
pH both accept: 4–7.5
Hardness both accept: 1–12 dGH
Keeping both needs at least the larger minimum tank, 14 US gallons (54 L), and that is a starting point, not a stocking plan.
Frequently asked questions
Which is easier, a neon or a cardinal?
Our data rates both as easy. We found no source that compares their hardiness directly. Seriously Fish says maintaining cardinals generally presents few problems, but that wild fish need more careful water management, and it warns about ill-health in farmed neons.
Can neon and cardinal tetras live together?
Our compatibility rules rate them a good match. Check that your temperature sits inside the range they share, shown in the table on this page. We found no source on whether they school together, so do not rely on it. Keep a full group of each.
Are cardinal tetras bigger than neons?
A little, on our data. See the table on this page. The difference is small, and both need the same minimum tank and group on our species pages.