Bluefin Notho (Nothobranchius rachovii) Complete Care Guide

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 Castle Dawn Aquatics Fish of the week Nothobranchius rachovii

Nothobranchius rachovii is native and widely distributed throughout South Africa.



Nothobranchius rachovii is one of 90 species from the Nothobranchiidae family which are native to South Africa and can be found throughout its vast regions.

Out of all the species in the Nothobranchiidae family, Nothobranchius rachovii is the most prolific in the aquarium trade, and a firm favourite among aquarists due to its striking colour and ease of care.

What makes Nothobranchiidae family unique is their annual life cycle which is still shrouded in myth to this very day. In the wild, the species would often be found in small bodies of water which would eventually evaporate under the harsh heat of the African dry season.

As the rain falls after months of drought the small dried out pools fill with water and the Nothobranchius would magically reappear. This strange occurrence feed a common belief in the locals that the fish came down with the rain and were often referred to as Rain fish.

The miraculous event of the Nothobranchius dying and reappearing with the rain was not the result of fish falling out of the sky, but was down to the Nothobranchius remarkable ability to survive the harsh environment.

Nothobranchius are not only prolific at producing offspring but they also grow at an extraordinary rate and are sexually mature in as little as 2 months, all evolution traits to beat the fated drought.

The most remarkable evolutionary survival trait of the Nothobranchius is how they spawn. As the Nothobranchius spawn, the male and female dive to the bottom of the pool depositing their eggs deep within the substrate. 

As the water of the pools evaporates the adult Nothobranchius die. However, the next generation is safely tucked away under the now dried up floor of the pool, protected from the harsh heat of the dry season.

As the ground dries and cracks the eggs become exposed to the air and when the first drop of rain begins to fall, replacing oxygen with water (anaerobic conditions) it kickstarts the hatching process and the cycle of life begins anew.


Nothobranchius Rachovii Care Summary

Scientific Names:

Nothobranchius rachovii beira 98, Adiniops rachovii

Common Name:

Bluefin Notho, African Blue Fin Annual



Maximum Size:

6cm (2.4")


Egg depositors

Sexual Dimorphism:

Mature males are more colourful.

Food & Diet

Live and Frozen foods.


 20-23 deg C (68-73 deg F)


 6.0 - 6.5. Prefer slightly acidic water.

Tank Size:

 Minimum 10 gallons per trio.


Maximum 12 months


Peaceful, males can be territorial with other male Nothobranchius.



Nothobranchius Rachovii Care


 Aquarium Setup:

The aquarium needs to be spacious, heavily planted with a loose or peat substrate. Add plenty of hardscape to the aquarium such as bogwood, leaf litter or aquarium botanicals to help keep the aquarium water soft, acidic and rich with tannins.

The hardscape also provides additional hiding places for males if more than one is present within the aquarium. Nothobranchius rachovii is peaceful however males can get aggressive towards each other.

Blackwater Aquarium Botanical Starter Packs Are Perfect For Creating a Biotope For Nothobranchius Annual killifish
Our blackwater aquarium botanical starter packs are perfect for creating a biotope aquarium for Nothobranchius rachovii.


Plant the aquarium with soft water-loving species such as Java fern, Java moss, dwarf Sagittaria, Cambomba and Ludwigia. If you wish to create a biotope aquarium with plants commonly found in the Nothobranchius rachovii natural habitat use species such as Utricularia, lagarosiphon and ottelia.

PRO TIP:  If your main goal is to breed Nothobranchius rachovii, a glass-bottom aquarium with an introduced container of peat, will make things easier to remove the eggs after spawning.

IMPORTANT: Nothobranchius rachovii require an enclosed aquarium as they are Instinctual jumpers. In the wild, males can leap from their pools in search of bigger waterholes and females. 



Nothobranchius rachovii prefer little to no flow in the aquarium, so a small air-driven filter is best suited for the species. In the wild, Rachovii can be found in pools as small as an animal footprint, where the water tends to be stagnant, inherently making Nothobranchius rachovii unequipped to handle a strong flow produced by a power filter.

If Rachovii is kept in an aquarium with a strong flow they will quickly tire. The strong flow will drive Rachovii to become reserved, hiding away to shelter themselves from the strong current, which in some cases can result in premature death.

At Castle Dawn Aquatics we use our air-driven bio sponge filters in our Nothobranchius tanks. They produce excellent filtration without a heavy current and are perfect for not only Nothobranchius but other Killifish and delicate species such as Licorice gourami.



When it comes to lighting Nothobranchius rachovii prefer lower light temperatures of around 4500K. High-temperature direct lighting in the aquarium simulates the sun at its peak and can cause the Nothobranchius rachovii to go into jumping fits. 

Although in an aquarium the Nothobranchius rachoviis instinct is to jump and leave in search of another water pool before its current one (Your aquarium) drys out.   Nothobranchius rachovii can end up damaging itself on the aquarium lid, or find itself in a fatal position on the floor of your home.


Water Parameters:

Nothobranchius rachovii prefer slightly acidic water and are comfortable in a pH between 6.0 – 7.0 with a water hardness somewhere between 5 and 20 dGH. This can easily be achieved by employing natural products like Castle Dawn Aquatics Aquarium Peat Filter Media ''TURF'' or aquarium botanicals.

Castle Dawn Aquatics Creation TURF Organic Peat Water Softening Pellets Will Make Water Conditions Perfect For Nothobranchius rachovii
Castle Dawn Aquatics Creation TURF is organic peat pellets which will help create the natural water conditions of Nothobranchius rachovii.


The species is not overly challenging when it comes to water parameters and out of all the old world Killifish, they are capable of handling the majority of beginners mistakes. If you intend of keeping the species at their preferred pH of around 6.0 avoid using CO2 which can lower the pH to dangerous levels.



In their natural habitat Nothobranchius rachovii deal with extreme temperature fluctuations as they rapidly change throughout the day ranging between 16 – 32 degrees celsius.

In the aquarium keep Rachovii at a stable 23 degrees celsius which is a little cooler than the typical community tank. The logic behind this is due to Nothobranchius being an annual species thus warmer temperatures accelerate their growth shortening their lifespan.

Keeping Nothobranchius rachovii in colder water than 20 degrees celsius the males will lose their colour which defeats the purpose of keeping these marvellous species.



Nothobranchius rachovii are micro predators and prefer live foods such as Grindal worm, Daphnia, White worm and baby brine shrimp. The females when sexual mature will produce eggs on a daily basis and require a high protein diet. Most will take frozen foods if live foods are not an option and some may even take dry foods.


Tank Mates:

Nothobranchius rachovii is best kept in a species only aquarium with one male to 3-5 females. Keeping multiple males with females can result in disputes between males fighting for the female's attention. The disputes between the males are not damaging and tend to end with a bruised ego and a few nipped fins in most cases.

If Nothobranchius rachovii are to be kept in a community aquarium keep them with other Killifish species such as Aphyosemion striatum or austral. Species like corydoras and dwarf gourami such as Honey gourami all make ideal tank mates.



Sexual Dimorphism:

Castle Dawn Aquatics Fish of the week Nothobranchius rachovii Care Male and female

The difference between male and female Nothobranchius rachovii are clear. 

The difference between males and females when it comes to Nothobranchius rachovii is like night and day. Males are extravagantly coloured and patterned whereas the females are free from any vivid colours or patterns.


Setup and Mating:

To breed Nothobranchius rachovii place a male and at least 3 females into a small aquarium (5 gallons) that possesses a container of peat substrate about 2 inches deep.

The male will put on a flamboyant display to attract the females resulting in the allured female diving into the peat substrate with the male where the pair deposit the fertilized eggs.

The Nothobranchius rachovii pair will replicate the process over a period of a few minutes, resulting in several batches of eggs tucked away within the peat substrate.

Nothobranchius annual killifish breeding egg laying aquarium peat.

Castle Dawn Aquatics RIVERBED is the perfect breeding material for Nothobranchius Killifish.


Remove the peat from the aquarium allowing it dry to a point where it is slightly damp. Transfer the peat with the eggs into an airtight bag or container keeping it damp throughout, store it somewhere safe for up to three months.

Castle Dawn Aquatics Fish of the week Nothobranchius rachovii Care In The Home Aquarium Breeding (credit unknown).

Nothobranchius rachovii spawning in peat substrate.

After the 3 months put the peat/eggs into aged water where the anaerobic conditions will cause the fry to hatch in and around 10 days. The fry should be removed and placed in a well-planted rearing tank with soft acidic water. 

You can remove the peat/eggs and dry again for an additional week then repeat the process of submerging it in the water again, this will allow any stragglers to hatch that did not hatch the first time around.


Fry Care:

From the get-go, Nothobranchius rachovii fry will eat freshly hatched brine shrimp growing at a phenomenal rate with males and females clearly defined are 1.5 months.

Fry can be susceptible to fungus and water parameter fluctuations, making it important to siphon off any uneaten food and maintain the water quality. 

Do regular small water changes instead of large weekly ones to prevent any drastic shifts in the water chemistry which could result in the death of all the fry.

PRO TIP: Use our Castle Dawn Aquatics micro aquarium siphon which is perfect for fry tanks.



If Nothobranchius rachovii do not breed they will live longer.

This is false, they will die in and around a year regardless of whether they breed or not. Their short lifespan is a genetic adaption to survive their natural environment. 


Nothobranchius rachovii Conclusion

Castle Dawn Aquatics Fish of the week Nothobranchius rachovii Care In The Home Aquarium Conclusion


Nothobranchius rachovii is a great starter species for any beginner aquarist looking to break into the world of killifish. Their flashy colours are pleasing to the eye and although short-lived they will reward you with unique behaviours that most will never get to experience in their lifetime.

Resilient than most Nothobranchius species, Rachovii will forgive the beginners mistakes and a single breeding group can provide you with generations Nothobranchius rachovii for years. Just remember to keep that aquarium lid tightly closed ^_^.


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