Nothobranchius Rachovii - Beira 98

[BigC]

Breeding Nothobranchius rachovi - Beira 98
Pass the Magnifying Lens...please
​

Nothobranchius Rachovi - Beira 98​

Adult Male​

I forget how many times folks have asked me for help with hatching annual killifish species eggs bought from Far East breeding farms via online sources such as Ebay. I hope this little scenario, which happened to me recently, helps others who have unwittingly gone down the same route and acquired eggs which they were ill equipped to cope with. So it is with thanks to omese for giving me the opportunity to address this growing trend.

OK I usually start these threads with the sum of the whole. I usually tend to complete an opus start to finish before submitting the finished article for everyone's perusal. This time around, through a catalogue of events I'll be doing things a little differently, and logging certain (providing everything goes to plan) events on a day to day or weekly basis.

Let me give you a little background to the situation in hand. Ordinarily I would post a breeding article starting with the fish spawning, egg production, hatching, rearing of fry, so on and so forth. This time a situation was forced upon me somewhat on which I had to act.
Some time ago I was approached by a young lad who was interested in Killifish. Knowing very little surrounding their care and husbandry, he proceeded, like many before him to purchase some Annual species eggs from so called Far East breeding farms. He chose Nothobranchius rachovi (Beira 98) as his first species on which to start his new found hobby. Now as we all know, or should know, Rachovi is a very colourful fish, one that will rival a lot of marine species in that respect, but in no way is it, IMHO, a beginners species. Had he contacted me sooner I would have recommended Guntheri as a species on which to cut his teeth as it were. Anyway the sceanario played itself out and finding out that he was ill prepared for their imminent hatch (no food stuffs readied) he asked would I hatch the eggs for him. Not wanting to let the chap down I duly agreed to hatch the eggs and once successfully reared I would return him a couple of pair of which he was more than delighted. This gave him the opportunity to gather more information on the subject and be better equiped next time when it's his turn to give them a go. He sent me the eggs and the story progresses from this point onward.
I received the eggs and the first thing that alarmed me was the collection and hatching dates.

Collected 18/07/2010 - Expected 29/08/2010​

Now I know enough from breeding this species many times in the past that something was more than likely amiss here as the drying period for Rachovii (although you can warm store to force the diapause to quicken) is around 4mths give or take. (check the iris within the egg sac for an indication of hatching) Not entirely happy with this information I stored the eggs for a further six weeks than what was advised on the label. (still a very short diapause for RAC) but this depends a lot on the moisture of the peat and temperature of incubation.
Today I decided to wet the eggs for the first time.
So I made up some coolish water (68'f) in a small margarine tub, 1/2 tapwater - 1/2 rainwater and a slight sprinkle of salt to deter velvet.
Fry began hatching almost immediately so armed with my little torch and pipette I prepared to go hunting Rachovii fry.

It was at this point I realised "My Eyesight is getting worse with age"! I had totally forgotten how small these little beggars were, especially as they had the camouflage of the peat to help them evade detection. Next out came the trusty large magnifying glass and the hunting ground became a whole lot clearer. As of one hour ago we were up to 16 fry, not a lot you might say but there are more to be caught and I've retired for this evening to resume in the morning. I have no idea how many eggs were in the peat to begin with as those Far Eastern farms are notorious for dubious practices when sending precise numbers of eggs. So we'll see how many we eventually end up with in the first batch before re drying the peat.

For now, the fry are being fed paramoecium. Annual fry need to be fed immediately upon hatching. Whilst there will be a certain amount of infusoria available via the peat they will still need a hearty meal soon after. They are too small in the first stages to accept artemia nauplii so we need to offer microscopic livefoods to get them to the next stage.
That's were we are at this present moment in time, tomorrow's another day as they say, success, failure who know's what factors will come into play as we progress. That remains to be seen.
These fry are tiny in comparison to a lot of other Notho. species I've encountered.
I will hopefully embellish this thread further with images depending on the outcome of ongoing events. Once I can get them to the brine shrimp stage then everything should be plain sailing. Fingers crossed.
Regards
C

 

[Carlovel1]

This is a great journal, good luck!

 

[BigC]

Whilst the situation is developing please allow me to fill in some basic information surrounding this beautiful species.

Nothobranchius rachovii, belongs to the family of the Cyprinodontidae. This amazingly colourful Notho. was first discribed by by E. Ahl in 1926 and was named in honour of Arthur Rachow, a renowned pre-world war German aquarium pioneer.
There are many different strains of RAC known to the hobby today, some readily available, some fairly obscure. Most are pretty much unrecognisable from the colour pattern that we all perceive to be Nothobranchius rachovi. Although still classified as the same fish separated only by locality they bare little or no resemblance (in colour) to the "*normal coloured" Beira strain.
N. Rachovi's distribution area is pretty vast but predominately lies within and along the border and coastal areas of Mozambique with one particular location being found just across the border with South Africa.
Known populations are;
Beira 98
Kruger National Park
MOZ 03-2
MOZ 04-02 Mazimechopes River
MOZ 04-08 Lima River
MOZ 04-10 Nicuadala
MOZ 04-3
MOZ 04-9 Quelimane
MOZ 99-9
MOZ 99/1
MOZ 99/3
MZHL 05-5
Nhangau MT 03-4

This species of fish will attain a size of around 55-60 mm for the males with female remaining slightly smaller.

I wish to include (from published literature) a little description of Beira the main type locality of this species.
In Beira, the soil content is made up of salty red clay the coolest temperatures (average of 22.5°C - 72°F) can be found in July. During the hottest period (November-December) the average temperature reach 27.5°C (82°F). The temporary pools will start to dry out around May or June. The rainy starts in November, and by June -July most of the pools containing RAC will have totally dried out. The eggs of coastal RAC populations incubate in semi moist soils for approximately 5-6 months (hence my concerns over the hatching dates on the eggs supplied to me albeit the diapause times would be temperature dependant).
The area around Beira is made up of a great number of swamps and marshland which in-turn generates a unique micro-climate controlled by sporadic foggy night-time clouded areas which generate early morning dew, this stops the developing eggs from fully drying out.

These images show a RAC egg (from this batch) with still some way to go before hatching.
There is a fair amount of cell division with skeletal formation &
if you observe the second photo closely you may just be able to locate the eye.
This egg along with any others that are left in the peat will almost certainly need a further resting period before it's time for the fully developed fry to emerge.​

Often folks would often wonder what is termed by annualism or what does it mean that a specific genre or species of killifish is classed as an annual type. For the benefit of those enquiring minds I will attempt to briefly explain.
When we speak of the term annual killifish we are usually referring to a genre or species of Cyprinodontidae who's eggs require resting period in which to develop. Most annuals come from Africa and South America. They are fish that posses a very high metabolic rate. Their life-cycle is governed by climatic changes in weather patterns in their relevant geographical locations. Rains fill temporary water holes (sometimes only the size of a cattle hoof imprint) The eggs hatch out almost immediately and the tiny fry search for food. Annual species are constant eating machines and provision for a well stocked live food larder is a necessity when handling such species. They grow very fast, they have to as they will only have the time available until the hot sun dries their pool. They usually mature in around 4-6 weeks (sometimes shorter) and begin to breed, this is their sole occupation from this moment onward, (Normal lifespan for the Beira strain is between 9-12 months). At the latter end of this timescale the fish will look very ragged and a shadow of their former self.
As the pools begin to dry the egg develops normally until a specific number of cells has been reached then it will enter a resting stage or diapause (different species will have 2-3 different resting stages). These stages are again linked to the weather patterns of the area in which they live. When the rain starts to fall again the fry will hatch and start the cycle all over again. One point to note is that not all eggs will hatch at this moment incase of a premature freak storm, some eggs will be at differing stages of development and may not hatch (in the wild) until the following season. Nature has thought of everything to ensure the survival of such complex species of fish.
Must go and check these eggs and fry again.
Regards
C

 

[BigC]

Just finished checking the peat for any more hatchings and I can report another four have been transferred to the small rearing tub. That brings us up to around the twenty mark but I will keep the peat submerged for another 48 hours in-case there are any stragglers after which time I will re-dry and store the peat for a further 4-6 weeks and start this process again.
There has been no losses overnight I'm glad to say and I have performed the first of many minute water-changes using the same water make-up as before. This being agitated with 1 teaspoon of salt per 10ltrs of make-up water.
Water-changes are very, very important at this stage but they can also be fatal if you use a different chemical balance. It is good practice to make up around 10 extra litres of water specifically for use with this species when you first wet the eggs. Small and frequent daily water-changes are best, and I would only like to change around 30mls per day at this point. Later we can increase the amount of change. Always remember to keep the tubs clean, this is paramount.

Images of day old Nothobranchius rachovii Beira98 fry by the Author.​

So for now at least everything is going to plan, next step will be to increase the feeding regime and introduce microworm followed shortly after by newly hatched brine-shrimp. When I say newly hatched I mean exactly that, as Artemia nauplii can double in size after 24 hours and loose quite a lot of nutritional value in the process which is negative of what we want.
On we go!
Regards
C

 

[BigC]

The Rachovii fry are now approx one week old.​

They are feeding on Brineshrimp nauplii/Microworm 3 times per day with no problems. 50% waterchanges are being performed daily with the same chemical make up as they were hatched in.
I have lost one straggler in this process, there are, as always a couple more who are not keeping up with the pace so I will allow them a couple more weeks before the cull. Heartless I know but there's no use keeping sub-standard fish.

Today I redried the peat in the hope for a second hatch.

First the peat was strained through a fine mesh net then placed on some absorbent tissue and allowed to dry out somewhat to the consistancy of rolling tobacco. Finally the peat is bagged and sealed with a little air. After labeling, the packet is then stored in an dark warm place for a further 2 weeks, whereby the peat will be re-wet.
This is normal proceedure when dealing with any annual Killi eggs, and one would expect to get some more fry from the second hatch, possibly even surpassing the first. As these eggs were originally from the Far East the liklihood of obtaining a good second hatch must be questionable, but we'll wait and see.
Regards
C

 

[VaegaVic]

Fascinating!
I've always been interested in these fish, especially this particular species.
I've never found any real information on them that I've actually found helpful so this is a gold mine to me.

Could you tell us a few more things about this species? Mating habits? Sexual dimorphism? M:F ratio?
Anything not already stated would be helpful

 

[Biulu]

Hi Colin! So if I understood well from your description, you only feed the fry 2 - 3 days of micro food? And after that you continue with microworm and subsequently the artemia?

Are these fry basically doubling in size within 1 week? Your pictures are very clear, but there is no measurement attached, so it is difficult to guess the initial size and then the size after 1 week...

 

[BigC]

So if I understood well from your description, you only feed the fry 2 - 3 days of micro food? And after that you continue with microworm and subsequently the artemia?

You are correct in your assumption. These fish grow very quickly they are annuals so they have to. They posses a very high metabolic rate and are constant feeders. Now feeding 3x per day.

Are these fry basically doubling in size within 1 week? Your pictures are very clear, but there is no measurement attached, so it is difficult to guess the initial size and then the size after 1 week...

Yes, well almost. Basically you can feed the fry one day and return to the tubs the next and visually notice a change in the size of the fry, its that quick. They should be coloured up and breeding within 8-10 weeks. The following images should give you some sense of scale, the small fry is at the top of the spoon.

Photos courtesy of A.Taffe show Rachovii fry on a medicine spoon.​

I will post an update later today
Regards
C

 

[KittyKat]

/me wants an update!

 

[BigC]

Sorry long overdue, been very, very busy at work and will surely update asap. (this weekend)
thanks for looking
Regards
C

 

[BigC]

One month in and things really have really moved on a pace since my last insertion on this thread. Since the last entry I have managed to perform a cull which involved removing the weakest of the batch we are now down to around 12 decent individuals of which there are 4 males and 8 females, so that worked out well, and I am about to re-wet the peat for a second time. I have transferred the fish from various sized tubs into their own dedicated tank. They are feeding on Artemia nauplii and Grindalworm at present with a view of moving them on to Daphnia, Whiteworm and Gammarus shrimp soon. The males are fully coloured up now and are starting to establish a pecking order. A few minor squabbles developing but nothing major. The males are around 22mm in size with the drab females a little smaller at around 18mm.

It's getting hard to take a really good shot of the juveniles at the moment as they are a little skittish but they will become bolder as they grow.

So the program is still on track and I hope to be breeding these very soon, although I may decide to bring in some females of the same strain from a different source to strengthen the gene pool.
Regards
C

 

[BigC]

The fish are now growing at pace and I will soon have to introduce a pot of peat into their aquarium (in the next week or so) to provide them with somewhere to deposit their eggs. Of the four males, one is a cracking fish, very well marked and good body shape. This will be my main brood male for subsequent generations. I have developed a love for this little species once again and may decide to keep and breed these long term. They are a little finicky to hatch and feed the fry but it's well worth the effort when you see the resulting males.
Pics to follow....

 

[BigC]

Re-wetting the peat after a few weeks yielded only 5 more fry. Not a great result but it was performed just to show that it is possible to have more resting eggs within the peat mass which have not finished their diapause stages. It is now time to set the original batch up with a view to breeding. There is no time to waste, annual killifish mature quickly and will soon be ready to breed.
The substrata that I like to use for breeding annual killifish species is peat, in pelleted form. You can purchase these from your local garden centre.

I like to use plastic receptacles such as the image above. I place one pellet into the pot and add some tank water , the pellet will now swell and become waterlogged. It is now ready to be slowly added to the tank.

The males are now forming a hierarchy and the dominant male is trying to spawn with the females so we now need to add some medium for them to deposit their eggs into.
Nothobranchius rachovii are what we term as peat ploughers rather than actual divers such as some of their South American counterparts. The male will drive the female into the peat medium from above and behind, he will wrap his dorsal and anal fins around the female and shimmer until you will notice a slight "jerk" motion at this point a single egg will have been deposited just below the surface of the peat and fertilised by the pressing male. The female will then be released. The male will either perform the same act with the same female again or he will chose another. Either way this will become a continuous cycle of events from now until the fish expire.

 

[stevereade]

Seeing as you know your Killi's so well I was wondering if you could answer a couple of questions if thats ok? I have hatched and kept Killi's twice with random results and after reading this journal was thinking of trying this species.

What are the best parameters for the water once raised to adults?
I know when you buy eggs they come with brine shrimp hatching kits but do most lfs's sell the other foods?
Can you have peat as the entire tank substrate from hatched depending on current or is a mixture best?

 

[BigC]

Hi Steve,
I'll take your queries in turn if I may

I have hatched and kept Killi's twice with random results and after reading this journal was thinking of trying this species.

Whilst it is fine to assume that Nothobranchius rachovii is pretty easy to hatch and rear it is not always the case. This species alone is always first on the wanted list because it is so colourful. It is also responsible for why most novices shy away from annual killifish due to their initial failings. By all means give them a go but please take note of what I relate to in the rest of this reply. There are easier Notho species and I would advocate GUE (Nothobranchius guentheri) as a first foray into breeding African annuals.

What are the best parameters for the water once raised to adults?

My estimation for water parameters, as with most killifish sp. I try to move on/sell (to novices or shops) The water should be as close to a neutral pH as possible probably around 6.8. Their water would be moderately hard with a trace of salt.

I know when you buy eggs they come with brine shrimp hatching kits but do most lfs's sell the other foods?

Most LFS would not sell small livefoods, for these you would need to seek out specialist breeders and ask for starter cultures or search the internet for such. The amount of artemia cysts provided in those so called kits would only be enough for one hatch, maybe a two day feeding. You will need to purchase a lot more eggs and hatch on a daily basis. I dont know why they supply artemia cysts with Notho sp. that have relatively small fry because you cannot start RAC fry off with brineshrimp. Rachovii fry are much too small for them to feed on artemia. RAC need Infusoria/Paramoecium for atleast 2-3 days after hatching before going on to newly hatched brineshrimp. By newly hatched I mean just that as brineshrimp almost double in size 24 hours after emerging from the cyst. This is why most folks lose RAC in the early days. Losing a batch of RAC fry can usually be pinned down to one of three things, "starvation" by not adhering to what I have stated above, "Velvet disease", of which harder water with added salt will help prevent. Finally... "poor tank or fry tub maintenance", which is preventable by being meticulous about water-changing.

Can you have peat as the entire tank substrate from hatched depending on current or is a mixture best?

I'm not sure I understand what you mean by "from hatched" but I will attempt to answer all the same.
There is nothing stopping you from having the entire base of your breeding aquaria covered in peat, the only problem with that is when you come to harvest and store the egg laden medium it will be full of gunk such as uneaten food and fish waste, it is better to provide them with a small receptacle containing the spawning medium and let the fish utilise that. It makes tank maintenance and harvesting much easier.
A breeder will be harvesting the peat from annual killifish sp. on a weekly to fortnightly basis at least, as any longer would mean being faced with hatching a large batch of fry at the one time. Secondly if a breeder were to inadvertently loose an entire batch of fry for whatever reason then he/she would still have eggs in reserve. Having a large batch to contend with may or may not present the breeder (not selling eggs) with space problems, size & numbers in batch aside and depending on the sex ratios, the males of certain species will become very aggressive toward other males and will need to be separated if this trait becomes a significant problem.
I hope that helps
Regards
C