Rainbow darter Care Guide: Diet, Tank Mates, Diseases, Breeding & More

Updated: December 2, 2022

The rainbow darter is a beautiful and unique freshwater fish that is perfect for any aquarium.

They are peaceful and easy to care for, and make a great addition to any community tank.

However, they are also very sensitive to changes in water quality and parameters. This means that they require a bit more care than some other fish.

In this guide, we will teach you everything you need to know about rainbow darter care. You will learn about their diet, tanks mates, habitat, and more!

Species overview

Rainbow darters (Etheostoma caeruleum) are found in the central and eastern United States, primarily in the Mississippi River basin.

They prefer habitats with plenty of plants and hiding places, as well as a moderate current. This is something to keep in mind when setting up their tank.

Rainbow darters are mostly peaceful, although they can be territorial with their own species. They are also known to eat smaller fish, so it’s best to keep them with fish that are too large to fit in their mouths.

These fish are named for their bright colors, which can include a mix of blues, greens, yellows, and oranges. This makes them a popular choice for many freshwater aquariums.


Rainbow darter

The first thing you’ll notice about this fish is their bright and vibrant colors. As their name suggests, they have a beautiful rainbow hue that really makes them stand out.

The colors on their body are separated into a few different stripes. The base color is usually a light silver or white.

This is then followed by a stripe of blue, green, yellow, orange, and finally red. This coloration can vary slightly depending on the specific fish and their location.

The fins on a Rainbow Darter are rather long in comparison to their body. The dorsal fin starts about two-thirds of the way back and extends almost to the end of the fish.

The caudal and anal fins are both forked and begin closer to the middle of the fish. The pectoral fins are on the shorter side and start close to the head.

All of the fins have a beautiful rainbow hue that matches the body.


The average lifespan of a rainbow darter is 3 to 5 years.

Rainbow darters are relatively short-lived fish. A variety of factors can impact their lifespan, but the main one is water quality.

These fish are very sensitive to changes in their environment and even a small fluctuation can cause stress. That stress can lead to disease and an early death.


The average size of a rainbow darter is about 2.5 inches long. Males are typically a bit larger than females, but not by much. These fish are relatively small, so they don’t need a lot of space to swim and be happy.


Tank Size

The recommended tank size for rainbow darters is 10 gallons. If you’re planning on keeping more than one fish, you should add an additional 2 to 3 gallons per fish.

While rainbow darters don’t grow to be very large, they are active swimmers and prefer to have a lot of space to move around. They also like to hide in plants and other aquarium décor, so it’s important to give them plenty of places to explore.

Water Parameters

The rainbow darter is a freshwater fish that is found in the United States. It is a fairly small fish, only reaching about 2.5 inches in length when fully grown.

This fish is very colorful, as its name suggests. The body is primarily yellow with dark stripes running vertically down the length of the fish. The fins are bright red, which really makes this fish stand out in a crowd.

The rainbow darter is a very hardy fish and can tolerate a wide range of water conditions. However, to ensure the health and well-being of your fish, it is important to maintain the following water parameters.

  • Water temperature: 65 to 75 degrees Fahrenheit
  • pH levels: 6.5 to 7.5
  • Water hardness: 4 to 10 dGH
  • Alkalinity Levels: 4-8 dKH

What To Put In Their Tank

Rainbow darters are a species of fish that come from North America. They’re found in a variety of habitats but prefer slow-moving waters with plenty of vegetation.

When it comes to setting up an aquarium that’s suitable for them, you’ll want to recreate this as best as you can.

The substrate should be a dark color with plenty of small rocks and gravel. This will give them plenty of places to hide and feel secure.

As for plants, you have a few different options. You can go with live plants if you wish, but make sure they’re tough enough to withstand a little bit of nibbling. Rainbow darters are known to nip at vegetation (although it’s not considered harmful).

If you don’t want to deal with live plants then you can always go with plastic ones. Make sure they’re securely anchored in the substrate though since these fish will dig around a bit.

In terms of other decorations, feel free to get creative. Rainbow darters don’t have any specific needs so you can add whatever you think looks nice. Just make sure there are plenty of places for them to hide!

Common Diseases

Rainbow darters are relatively hardy fish, but they are still susceptible to the same diseases and illnesses as any other freshwater fish species.

The most common disease that these fish experience is ich. This is a parasitic infection that will cause white spots to form on the body, fins, and gills of your fish.

If left untreated, ich can be fatal. However, it is relatively easy to treat with the right medication.

Other potential diseases include bacterial infections, fungal infections, and parasites. These are all rather common in the freshwater aquarium world and can be treated with the proper medication.

As with any other fish, the best way to keep your rainbow darter healthy is to maintain a clean and stable tank. This will help to prevent any diseases from taking hold and will also make your fish more resistant to sickness.

Behavior & Temperament

The rainbow darter is a peaceful fish that is relatively easy to care for. They are not aggressive and will do well in a community tank as long as they are kept with other peaceful fish.

Rainbow darters are active fish that enjoy swimming in groups. They are not shy and will often be seen swimming in the open. They are bottom-dwellers and prefer to stay near the substrate where they can look for food.

Rainbow darters are not known to be fin nippers but they may eat small fish if they are small enough to fit into their mouths.

Tank Mates

Because of their small size and peaceful disposition, there are a number of different fish that work well as tank mates for rainbow darters.

These fish occupy the middle to bottom of the water column and prefer to stay near the vegetation. As a result, you’ll want to choose fish that occupy different levels of the tank.

Here are some compatible species that tend to do well:

  • Guppies
  • Platies
  • Mollies
  • Swordtails
  • Neon Tetras
  • Cardinal Tetras
  • Rasboras
  • Corydoras Catfish


The rainbow darter is a beautiful and popular fish that is relatively easy to breed in captivity. They are typically found in the eastern United States and Canada, living in freshwater streams and rivers.

In the wild, rainbow darters breed in the spring. The males build nests out of plant material, which the females then lay their eggs in. The males will then guard the eggs until they hatch.

To breed rainbow darters in captivity, you will need to set up a breeding tank. The tank should be at least 20 gallons and should have a sandy bottom. You will also need to add some plants and hiding places.

To trigger spawning, you will need to lower the water level and raise the temperature to around 75 degrees Fahrenheit. You may also need to add a bit of salt to the water.

When the female is ready to lay her eggs, she will do so in the plant material. The male will then fertilize them. Once the eggs are fertilized, the male will stay with them to protect them.

The eggs will hatch in 7-10 days. When they hatch, the fry will be very small and will need to be fed live food. You can purchase live baby brine shrimp or you can culture your own.

Once the fry are a bit older, you can start to feed them pellets or flakes.


The rainbow darter is a beautiful and unique fish that is perfect for the beginner aquarist. They are easy to care for and will add a splash of color to your tank.

If you are looking for a fish that is low maintenance and easy to care for, the rainbow darter is a great choice.