Belly Sliders

I have always had some belly-sliders at one stage or another, especially with annual killifish and Angels. It seems that one of the prime causes of belly-sliders, is bacterial growth in the tank. This can be combated in various ways, including water changes, wiping of the tank floor, using Silver, using Rooibos tea, using Indian Almond leaves, etc. Belly-sliders are apparently also caused by the use of methylene blue and acriflavin, both used to control fungal growth on dead eggs. I could write belly-sliders of as natures way of culling the weak, but sometimes it just affects too many fry for this to be a valid reason. So far I have used Rooibos tea and Oak leaves, both with promising results. (Of course with plenty water changes.) My next step is to try some Sterling Silver in the tank. It also seems that fry raised exclusively on MW, are more prone to belly-sliders than fry raised on BBS. I suspect it might be due to the yeast that the MW are feeding on, which get transferred to the tank with the MW at feeding time. I feed my fry up to 6 times per day, which does cause some pollution of the tank water, but I also do daily water changes. I have used Methylene blue on the eggs in the past, but I feel that the only real advantage of doing this, is to subdue the lighting. Black water extract, Rooibos tea, Oak leaves etc, will have the same effect, but is a lot safer. Is there anybody that can give me some pointers on the subject?

 

Hi Wickets,

The topic that you raise here is important, but it is actually very complex and requires a complex answer. I think that it is important that this is unravelled so that persons can understand this. However, I don't want you to get the idea that I am criticizing you for making these comments, the problem just simply is very complex and requires very specialized knowledge in order to understand this.

The causes for bellysliders in killifishes and angelfishes are firstly completely different and have very little to do with each other.

The primary causes for belly sliders are not bacterial problems, there are other reasons which are much more important.

Very often, persons do not search on TASA for previous posts, and I have posted before that methylene blue and acriflavin belong in the graveyard/museum of fishkeeping and should not be used at all any longer. Methylene blue does not work any more because all aquarium bacteria have adapted and become resistant to methylene blue because it was used so much particularly in the Singapore and Malaysia where most of our fishes come from, so it does not help to solve bacterial problems and instead is damaging for very sensitive tiny fry that are developing. Acriflavin is actually mutagenic and is therefore dangerous for small fry and should not be used either, it can cause all sorts of other growth deformities and permanent growth reduction problems as well.

Why do we want to use these substances? Because some bacteria are causing eggs to go rotten. Well I say don't treat the symptom, treat the cause. Stop the bacteria from multiplying and being in your tanks in high numbers. This can be done by adequate filtration and water management such as water changes and correctly prepared water. Don't try to treat with some or other chemical, get the water conditions right so that the bacteria cannot even develop as it happens in nature, this work much better.

So we must firstly ask, what goes wrong when we have bellyslider fry, what has caused this? The swimbladder is almost like a little balloon in the middle of the fish, with its opening linked to the gut of the fish. The opening is regulated by a muscle, called the sphincter muscle, which is almost like a cable tie and it closes the balloon so that it can remain inflated, or it can release the air into the gut and it is released from the vent (die poephol in plein Afrikaans). When a baby fish hatches from the egg, the swimbladder does not contain any air and it will drop to the bottom of the river or pond or aquarium. Then the blood transports oxygen to the swimbladder and it actually then forms a bubble in the swimbladder and once this happens the fish can actually swim in the water. For the rest of its life the fish can, so to speak, pump up the swimbladder via oxygen transported via the blood, or deflate the swimbladder by releasing air into the gut and passing it via the vent. If the swimbladder does not inflate in the fry then we get fry that cannot swim up from the tank and drop down again and we call the belly sliders. Adult fishes can also loose control over the sphincter muscle and then become belly sliders such as in discus, or not allow air out of it so that it remains overinflated and these fishes then tend to want to drift to the surface of the tank and they try to swim down and we call the headstanders. This is a common problem in discus. Please note that the swimbladder cannot inflate it a fishes goes to the surface and gulps and bubble which then moves down the gut and to the swimbladder. The swimbladder cannot open to allow a bubble in, it can only open and allow a bubble to go out.

The main reason why bellysliders are found in killifishes is because the embryo has developed in the egg, but it actually is not a mature fish yet. What one does is one dries out killi eggs such Nothobranchius and one puts them into peat so that they can develop slowly but surely and when they have fully developed, then one puts them into water and they can hatch and grow and become normal fishes. Now when we look at killi eggs that have been incubated in peat, then we sort of assume they are ready for hatching, add water and they hatch, but often they have actually not sufficiently developed yet. When this happens the swimbladder often has not developed enough and even if the fish hatches, the swimbladder cannot inflate, it just simply has not developed yet. The tiny fry cannot catch up and it remains a belly slider, and you cannot do anything about it. You have added water to the eggs too early and they cannot swim normally and grow normally, and will eventually die. This has nothing to do with bacteria it has to do with being able to identify when the eggs have developed enough to be hatched. Experienced killi keepers know when to do this, when you are a beginner you make mistakes and you can have all fry that hatch being bellysliders and this then means they will all die.

In angels and this also applies to discus, the causes for bellysliders are related to water conditions. If the water is soft and the pH is low, as it occurs in nature, then the swimbladder will inflate normally in the fry. This has to do with an additional factor and that is osmoregulation, which is regulated by the kidneys. In the tiny fry all of the functions are just starting to develop and are very sensitive and if the water is not absolutely correct then the fry don't develop normal osmoregulation and normal inflation of the swimbladder. Many of the angelfish and discus fry in a batch cannot develop normally in water that is harder (in other words in which there are too many dissolved substances such as calcium, magnesium or carbonate) or if the pH is too high, the swimbladder just simply cannot inflate normally, and then you get bellysliders. To correct this, you should soften the water through using a mix with RO water, or you should reduce the carbonate hardness and the pH through the use of peat and plant substances. Your comments about using oak leaves, catappa leaves, black water extract, and rooibos tea reduce carbonate hardness and pH and they add plant tannins which also protect against bacteria, but the effect the substances have on the bacteria is actually not what reduces the swimbladder problems directly, it is the effect they have on water quality which reduce the number of bellysliders. You come from Primrose, Germiston and your water has a too high pH and too high carbonate hardness for breeding discus and may just be soft enough for angels but this is on the border of being too hard, so you should try to improve your water conditions to reduce the water hardness.

So thanks for starting this thread and it is something that the discus fanatics need to read very carefully as well, but I hope that you can see that it is much more complicated than what you thought.

Kind regards,

Dirk

 

Interesting read. Thanks @Dirk

 

Thanks @Dirk. You have gone to great lengths to reply, and I really appreciate that. I will treat the water as you recommended. Just one more thing, is silver really a bacterial killer? I know that a piece of copper in the tank controls velvet with Nothobranchius, but does silver really work, or is it just another fable? I might add that I currently have 5 batches of Angels less than 3 weeks old, all on Rooibos, and not one belly-slider. I suspect that our water conditions might have improved due to all the rain? I assume that our rain is acid because of all the industries and mines, and thus lowers the pH? I have not measured the pH and I am just guessing here.

 

Hi Wickets,

No, I do not believe that silver is a bacterial killer.

I would STRONGLY advise against putting a piece of copper in a Notho tank as copper is highly toxic and will cause sterility. For keeping Nothos velvet free, the advice is to use salt, but also to very carefully check that the pH is alkaline. It may interest you but I am currently researching the phylogenetic relationships of Nothos mainly in Zambia and the Congo, using DNA sequencing and we intend to publish this somewhere in the New Year. However, the next question is whether I can supply Notho eggs and the answer is no, I do not keep any at the moment.

Re water conditions in Gauteng you have the problem that rand water adds Calcium Hydroxide to your water at their treatment plant. This makes the water alkaline and adds calcium and carbonate so they are working against the aquarist that wants soft water for his fishes. It may be that the water gets a little softer during the rainy season, but not due to acid rain, your water loaded clouds blow in from elsewhere. What happens is that the acid rain caused by the Gauteng pollution falls on the Okavango delta and there causes it to acidify.

I will not and cannot keep fishes any more without a pH meter. If you are breeding fishes you should really think about it. Also, you may be shocked to find how fast the pH drops if you have a tank full of young angels that you feed aggressively, the ammonia to nitrate conversion of course releases H+. In our soft water here in the Cape these pH drops occur all the time and without a pH meter, you would be killing fishes all the time. I would just simply not want to guess, it is far too risky.

Kind regards,

Dirk

 

@Dirk. How can I thank you for all the valuable advice? I have never been one to test water. I probably got away with it because I do heavy water changes. BUT... I am not to old to learn or change my ways. I'll get myself a pH meter and a hardness test kit. I did not know about the Calcium hydroxide either. I am not a chemist, so I can only assume that H+ is a Hydrogen Ion, and that it will form hydrochloric acid when combining with chlorine. I am sure that will drop the pH drastically. I don't keep a variety of Nothos anymore, so I promise I won't bug you for eggs. I do have some N.guentheri eggs though, if you should be interrested in some.

Regards

F

 

Hi Wickets,

When you want to buy a pH meter, be very careful not to buy a cheap one and not a pen type one. These have a cheap electrode which is not sensitive enough. Speak to Marco who is based in Pretoria as I gave him advice and he can tell you who a reliable supplier may be in Gauteng.

Yes the H+ is a hydrogen ion and higher amounts or concentrations of it cause acidity. It works on its own and does not need the chloride ion, when it is in water the H+, the hydrogen ion and the Cl-, the chloride ion separate and dissolve in the water and the hydrogen ion does "its thing" without needing the chloride ion. The more H+ there is in the water, the more the pH will drop.

Thanks for the offer of the Notho eggs, I am busy redoing my fish room completely and everything is on emergency measures so I cannot accommodate any more fishes at the moment.

Kind regards,

Dirk

 

Thanks Dirk. I have met Marco, and will PM him in connection with the pH meter. I nearly bought one of the pen types today, but luckily I was not happy with the way you calibrate it.

Regards

F

 

@Dirk. Just some feedback on my Angels. I now stick to the following routine and most of my fry survive and seem to be doing well:
I breed the adults in tap water, and remove the eggs to a 50/50 RO/tap water mix. No additives, such as fungicides are added, except for some Rooibos tea. I was worried about shock to the eggs with this change, but they hatch as normal. Fry are fed on microworms from free swimming until 2 weeks (from first day as egg, which is noted on tank). From 2 to 4 weeks, I feed both MW and powdered flakes. From 4 weeks, Powdered flakes only, as they don't seem to eat the MW from this size on. From free swimming until 4 weeks, I do daily water changes with 50/50 RO water, And remove all debris on the tank floor before each meal (4 meals per day). At 4 weeks, I switch the fry to tap water in large plastic drums, over a 24 hour period. From that size on, they seem to be OK. Unfortunately, my BBS hatches were extremely bad, as I think my cysts were old. I will now try to decapsulate them to try and salvage them, and feed them unhatched. If the 4 weeks seems a bit far fetched looking at the first date of this thread, please note that I had eggs and fry of different ages before I started this thread. All that said, this is the most successful I have been with Angel breeding, and I want to thank you again for all the valuable pointers you gave me.

Regards

F

 

Hi Wickets,

Glad to have been of assistance and I am glad that you are making progress.

If you could get the babies fed initially on freshly hatched brine shrimps you would see a massive influence on their growth rates, but you would also find that your adults would eventually also grow out a lot larger.

The decapsulation of the bs eggs is a schlep and unless you do it absolutely correctly, it will not work.

I have imported new brine shrimp eggs at the beginning of December and I could sell you some if you are interested. They will also not cost you a Sandton mansion, but they do have a 95% hatch rate. Once you use those, you won't look back. Send me a pm.

Kind regards,

Dirk