Diamond tetras are hardy, beautiful, beginner-friendly fish and got their name from their reflective scales.
These fish are quite popular because of their stunning appearance and how easy they are to care for. If you are looking for a fish that is easy to care for, yet still stunning, perhaps the diamond tetra is for you.
Appearance

Usual behavior
Diamond tetras are schooling fish, so they should be in a group of at least 6.They are generally peaceful and typically aren’t fin nippers if they are in school of at least 6.
Natural Habitat
Diamond tetras inhabit the slow-moving streams in Venezuela where the vegetation is thick.
They were originally found in Lake Valencia, located between the states of Carabobo and Aragua. Unfortunately, the quality of the water there is pretty poor, but that doesn’t mean they don’t need clean water.
Lifespan
The typical lifespan of diamond tetras is 3-6 years. However, as you may know, not every fish lives to its expected lifespan.
Remember that the fish’s environment can affect their lifespan. If the water parameters are off, for example, this can cause your fish to get stressed which greatly increases the chance of them getting sick and dying.
In other cases, it may be from a dirty tank or a lack of oxygen. There are many reasons why fish can die. This is why it’s so important to make sure your fish are healthy and thriving.
Size
The adult diamond tetra gets around 2–2.4 inches in length, so they don’t need a very large tank.
However, they should never be kept in a bowl. In fact, no fish should be kept in a bowl. It just isn’t large enough.
Diamond Tetra Care

It’s pretty easy to care for diamond tetras. These freshwater fish, surprisingly, rarely get sick, don’t need a very large tank, and can live in a variety of environments.
But, that doesn’t mean they don’t come with their challenges. Always be prepared to take care of the fish you own.
Tank Size
Because of their smaller size, these fish only need a 15-20 gallon tank, which is one of the many reasons why these fish are beginner-friendly.
Keep in mind, however, that the more fish you plan on keeping, the larger your tank should be.
Why do I always stress how important the tank size is? More fish produce more waste, which means the smaller tanks will have to be cleaned more frequently. However, if you have a larger tank, you won’t have to clean the tank as much.
If you have six diamond tetras in a 20-gallon tank, you won’t need to clean the tank that often, but if you have 20, well that’s a different story.
Tank Mates
You don’t have to be concerned about your diamond tetras bullying other fish in the aquarium. These fish are peaceful and rarely aggressive.
Never keep larger, aggressive fish with diamond tetras. They don’t mix well.
As I stated before, these fish aren’t fin nippers, as long as they are in a school of at least 6.Fortunately, they should stop if you add some more fish. If they don’t, they may need a larger tank.
Here are some suitable tank mates.
- Livebearers (i.e., mollies, swordtails, and platies)
- Rosy barbs
- Odessa barbs
- Celestial pearl danios
- Cory catfish
- Congo tetras
- Tiger barbs
Diet
It isn’t very hard to feed these fish. They should accept a variety of live and commercial foods.
These fish should have some live foods as well (like baby brine shrimp or daphnia) from time to time as they are packed with protein which these fish need to thrive.
Here are some foods diamond tetras can have …
- Flakes
- Pellets
- Freeze-dried or live foods like brine shrimp, daphnia, and bloodworms
- Blanched spinach and zucchini
Water Parameters
These fish don’t need very specific water parameters, but they do need softer water.
These fish should be in warmer water with a pH of 7.0 (or neutral).
- Water Temperature: 72 to 82 degrees Fahrenheit.
- pH: 6.0-7.5
- Hardness: 4-8 KH
Common Diseases
These freshwater fish usually don’t get sick, but as you may know, no fish is immune to disease.
Diamond tetras can get common diseases such as Ich, skin flukes, bacteria diseases, and parasitic infections (i.e., protozoa and worms).
If you want to keep your diamond tetras healthy and thriving, check the water parameters frequently. A sudden change in water parameters will often make fish stressed which often leads to sickness!
Typical Price
These fish are around $3-4 USD, but it depends on the seller. Some may sell their diamond tetras for more, while others may sell theirs for less.
FAQ
Here are some questions related to diamond tetras.
Do Diamond Tetras Need A Heater?
The short answer is yes. Diamond tetras do need a heater. Typically diamond tetras can’t live in room temperature water.
Are Diamond Tetras Aggressive?
No, diamond tetras are usually peaceful. The only time you need to look out for aggression is during mating season. During this time, the males may get a bit aggressive.
Breeding
Breeding these fish is fairly easy. However, the biggest challenge is finding a breeding pair (or pairs). You see, the pair should be the same age and size. This can be a bit tricky.
Males are typically brighter and more colorful than the females. Females with eggs will have a rounded stomach.
Diamond tetras can be spawned in one or six pairs. How many should you spawn? Well, it depends on how many eggs you want.
The breeding tank should be a 20-gallon aquarium. The water should be warm (around 78°–84° Fahrenheit or 25.5–28.8 ° Celsius) and the pH should be slightly acidic (around 5.5–6.5).
The water in the tank has to be clean, so filtration is essential.
There should also be something for the female to deposit her eggs. Java moss should do fine.
When you add your breeding pair(s), make sure all the lights are off. Then slowly increase the light levels again. This should trigger the spawning process.
Don’t worry if your pair(s) don’t start breeding right away. Spawning could take up to 2 days.
Once the spawning process is over, immediately remove the breeding pair(s). If you don’t, they will eat the eggs!
The eggs should hatch in the next 24–36 hours. After around a few days, when the fish become free-swimming (they will feed on the egg sac for around 3 days), feed the fry baby brine shrimp or infusoria.
Are Diamond Tetras for Me?
If you want a beautiful, small tetra, then maybe diamond tetras are for you.
Diamond tetras are hardy, peaceful, which makes them a great beginner-friendly fish. They can also thrive with a variety of fish. Just make sure these tetras aren’t with larger, more aggressive fish.
Resources:
Aquarium Source
Diamond Tetra 101: Care, Tank Mates, Size & More!
Fishkeeping World
Diamond Tetra Care & Species Profile
Meet The Pet
Diamond Tetra (Moenkhausia Pittieri)
Wikipedia
Fish Laboratory
Ultimate Diamond Tetra (Moenkhausia pittieri) Care Instructions
Life Of Fish
Diamond Tetra Must Know Care Facts, Behavior, Breeding
Fish Tank Advisor
My Aquarium Club
A Diamond In The Rough: Diamond Tetras (Moenkhausia Pittieri)