FIA is community supported website. When you purchase through links on our site, we may earn an affiliate commission. Learn More.

Rivulus Overview, Care, Tank Setup & Breeding Guide

Rivulus is one of the most popular killifish species which offers fun and beautiful characteristics in the community tank. Many aquarists are fond of the Rivulus because of its amazing coloration, which is evergreen. No one can be bored with the beauty of the rivulus.

This fish is amazing both in the daytime and at night. As you wake up, you will enjoy the light shining from the fully grown males of the fish. If you are a community tank lover, you won’t regret your decision to add this fish to your community tank.

Species Overview

Level of CareBeginner – Intermediate
AppearanceLive-colored with a flat back body, rounded tail fin, and small black dots on the body
Life Expectancy2 – 4 years
Size1.5-4 inches
Tank Size20 gallons
Tank EnvironmentGravel, sand, or quartz, dense plants. 
Tank Mates Tetras, Danios, Mollies, Platys etc.

Rivulus is a species of Killifish. It is the jewel of the South American territories. Also called blue striped killifish, it comes beautifully with a unique look and coloration.

Behavior & Temperament

The peaceful fish can be paired with other peaceful tank mates who are familiar with the other species too.

When added to the community tank, they tend to be indifferent towards the other tank mates. But they can be territorial if their spaces are affected by the other fish.

For the vibrant dwellers, you could prepare a larger tank to cater to all the needs of the species. Although they are natural jumpers, they can jump when there are slits on the top of your tank.


The blue-striped rivulus fish has an elongated body with a rounded caudal fin. You will notice a thick black stripe that crosses the length of the fish behind their eyes.

The neon blue line is located at the border above the black band. The rest of the tail is bright orange. The females have light blue coloration with a dark line crossing the length of the body.

Most killifish, including rivulus, have round scales and a slender shape. Their body shape gives them the advantage of swimming. The long-flowing fins can end in a point. They can grow from 3 to 10 inches in size. But in captivity, it is rare to see them reach 10 inches.

Natural Habitat

Rivulus fish originate from French Guyana and Brazil. They are natives of South America. These fish flock to various water locations, including rivers, brooks, creeks, as well as streams.


This small killifish species is available in many breeders’ stores. You can easily find them in your local pet stores. Each killifish can cost between $2 and $10 per fish. The breeders will offer you a wide array of fish based on their sizes, colorations, and other variables. Depending on those variables, you could spend more or less.

Consider comparing one store to another first before proceeding. For a group, you will get them for a cheaper price. The breeders will offer you a better deal when you purchase a group of specimens in a group.

Tank Setup & Care

Caring for this fish is as easy as caring for any other peaceful fish you add to your community tank. The fish tend to jump up from the water and catch the insects as their food. They also love to hide and play in the floating plants and tall plants. They can also dart around the spaces of the tank in a split second when they find something to eat.

To prevent them from jumping out of the aquarium, you will want to install a tight-fitting lid on top of your aquarium. Consider this as one of the first tasks you do to keep your fish safe. It will also prevent you from having a hassle saving your fish from the carpet or floor.

Tank Size

A group of two to four small killifish buddies will need at least a 20-gallon long tank. The larger the group you add, the more gallons you will need to prepare. You add 30 gallons or more for a larger group of rivulus in your community tank.

Water Parameters

The temperature should be around 72 to 75° Fahrenheit. Consider maintaining the° of the aquarium in that range to keep it healthy and well.

Also, you need to consider their tank mates. It is much safer to tag them along with tank mates that can tolerate the same range of temperature. The pH range is between 5.8 to 8. You can use this range to include other similar-sized tank mates.


The substrate can be easier for your rivulus killifish. No matter what substrate you choose, your small buddies won’t protest much. The substrate choice can be gravel, sand, or quartz. It is up to you.


These killifish species are best to dwell in a heavily planted tank. You can add live plants and/or floating plants. The combination of dense vegetation can be a great idea since this will contribute to the strong flow inhibitors. Your fish don’t like the strong water currents.


The lighting should be dimmer. They inhabit a water area that has a good level of shade. In some cases, they don’t even need artificial lighting. If the area is too dark, you could then consider purchasing a low-powered light fixture.


Many big filters can cause strong water currents and flow. These are not good options for your small fish. Instead, you could use a sponge filter that can work for a smaller tank. The water flow should be slower.

Rivulus xiphidius

Rivulus Tank Mates

These killifish species are indifferent towards other fish. For that reason, you can also add them to a community tank. They are peaceful enough so that no one wants to bother them.

If you choose to tag them with the other fish, you will want to add more gallons to your tank. Also, make sure that you only focus on fish that are similar in size to your rivulus.

Too big tank mates will eat your rivulus. Meanwhile, too small fish will be eaten by your pet. Don’t pair them with aggressive tank mates. They tend to escape from your tank when encountering aggressive mates in their tank.

Here are the best tank mates for your river:

All in all, the rivulus fish are peaceful and can live together with their tank mates in a peaceful environment without any problems.

They will do great in the community tanks. If you have just started the aquarium, you will want to keep a pair of killifish in the species tank.

If you don’t want to risk your fish brawling with another fish, you could use a dedicated tank to treat your killifish instead.

If you have large groups of killifish in one tank, you will want to make sure to create hiding places to prevent them from having a dispute over territory.

On most occasions, they don’t have any willingness to bother other fish in the same tank. But it is much better to keep small shoaling fish as larger groups will need larger tanks as well.

Food & Diet

Rivulus ornatus

In their natural habitat, they eat crustaceans, worms, and insect larvae. The best approach to feeding them is to mimic their natural activities.

Therefore, it is much better to provide live food for your fish. You could also get frozen foods if there are no live foods on the market.

Live foods can be fed daily. But you can also mix these diets with dried foods like flakes, pellets, and so on. It would be best to mix the different foods to improve the nutrient intake of your fish.

Live and frozen foods are very delicious to them. You can give them twice a day. Do not feed them too often.

Protein-based foods like insect larvae and crustaceans are the best. If you can get the worms, it can be a great option too.

However, make sure to keep good hygiene when giving them the worms.

Bloodworms could trigger allergic reactions to your skin. You can clean your hands after feeding your fish.

Breeding Guidelines

It is relatively easy to differentiate between genders. The males are larger and their coloration is more vibrant. Meanwhile, the female blue-striped rivulus has a duller color. Their size tends to be smaller.

It is easy to breed rivulus in your tank. The species in trios are recommended. Don’t mix these fish with the same species when spawning. The problem arises when the eggs are laid. The other adults tend to consume some of the eggs.

water should be slightly more acidic with a slightly higher temperature. Keep feeding them with a good mix of frozen and live foods. Choose a healthy male and female.

To maximize the results, you will want to prepare the spawning tank for them. Add the couples to the spawning tank.

The fish will then lay their eggs on the plants. You can have a bare-bottomed tank with a good medium.

When the water and tank conditions are right, spawning will come naturally. Move the parents to the main tank so that you can incubate the eggs.

The water should be shallow so that the fry can survive. You can add more water levels when the fry has grown exponentially.