Good tank mates for neon tetras are small, peaceful fish that like the same water: roughly 70 to 78°F, soft to moderately hard, slightly acidic to neutral. Goldfish are not one of them.
Goldfish prefer cool water (about 50 to 70°F, and they can live without a heater), while neons are tropical. Goldfish also grow large, eat anything that fits in their mouths, and produce a lot of waste. If you were searching “can goldfish live with tetras”, the answer is no.
Which fish are good tank mates for neon tetras?
| Tank mate | Fit with neons | Notes |
|---|---|---|
| Cardinal tetras and other neon tetras | Good | Keep schools of at least 6, preferably 8 to 10 or more. |
| Harlequin rasboras | Good | Peaceful schoolers, similar size and water needs. |
| White cloud minnows | Good | Tolerate the cooler end of the neon range. |
| Cory catfish | Good | Bottom dwellers that keep out of the neons’ way. |
| Kuhli loaches | Good | Shy and peaceful; give them hiding places. |
| Plecos | Good for small species | Common plecos get too big for a neon tank. Choose a dwarf type such as a bristlenose. |
| Guppies | Good | Similar temperature range and peaceful. Watch for fin nipping from pushy males. |
| Mollies | Use caution | Mollies do best in hard, alkaline water (pH 7.0 to 8.5), which is at the edge of what neons tolerate. |
| Bettas | Use caution | Often fine in a 10 to 20 gallon tank with plenty of cover, but some bettas chase or nip. Be ready to separate them. |
| Angelfish | Not recommended | Angelfish may eat small tetras, especially as they grow. |
| Discus fish | Not recommended | Discus are usually kept much warmer than neons prefer, and are shy fish that need calm tank mates. |
| Goldfish | No | Wrong temperature, will eat neons, heavy waste. |
What should you check before adding tank mates to neon tetras?
Match temperature, pH and hardness first. Neon tetras are listed at roughly 70 to 77°F, pH 4.0 to 7.5 and 1 to 12 dGH, and they need a tank of about 14 gallons or more for a school.
Next, check size. A fish that can fit a neon in its mouth, which is about 1.2 inches long, will eventually try. Keep neons in a group, since they are schooling fish and get stressed alone.
Finally, don’t overcrowd the tank. Neons are sensitive to poor water, so test regularly and keep ammonia and nitrite at zero and nitrate low.
Can neon tetras live with goldfish?
No. The temperature gap alone rules it out: warm enough for neons stresses goldfish, and cool enough for goldfish stresses neons. Larger goldfish will also eat tetras.
Why are neon tetras hard to keep alive?
Mostly because they are sensitive to poor water and easy to stock wrongly. Neons need ammonia and nitrite at zero, a school of at least 6 (8 to 10 is better), and a tank of about 14 gallons or more. Aggressive or oversized tank mates and sudden water changes add stress. Neon tetra disease is also hard to treat once advanced, so quarantine new fish.