discus

And, I sort of went of track there, with regards to Heckel cross, and please correct if wrong. In my searches I found that most feel the Heckel bars gets expressed in all offspring, so what I've read is that the bars are 'dominant'. I understand Snow whites to be exactly as you have explained, so that seems correct. Now that is where I get confused. In another discussion I read though that the Snow white gene is 'recessive', and it was said that it is like Blue diamonds in that way. What I then do not understand is what this ALL means!?! To my little understanding some fry will resemble mom, some dad, and a number will be a mix of the two with dominant genes prevailing? Am I totally bonkers and way of track here. . .or is just even more complicated than even that?

 

Hi Marco,

This is discussion is getting heavier and heavier....

OK, I could not get to that link about the basic genetics, perhaps you must check it please.

The article from science direct, tells you nothing about colour inheritance it only analyses genetic variability.

I do not have the Singapore discus book so I cannot read that unfortunately.

The snakeskins that you saw are not a new line, red colour based snakeskins are either called red snakeskins or else names like Oriental Dreams and Eruptions. I have attached a pic of an Eruption. Essentially these are snakeskin leopard discus. These fishes do not breed true and will always produce some non-snakeskin offspring on other words in this case some normal leopards, but who minds, leopards are also stunning!

Kind regards,

Dirk



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Hi Marco,

With regard to your Heckel bar inheritance question, I would say that you are correct that Heckel bars are dominant. Pics in Dr Schidt Focke's book show first generation crosses that have bars.

I would also expect that you are correct about the Snow White gene being recessive. But this is a different gene to the "barring" gene, this is a gene that specifies whether any colour will be shown whatsoever.

What you have said is quite correct: "Some fry will resemble mom, some dad, and a number will be a mix of the two with dominant genes prevailing?"

You are dealing with two genes here, the one gene specifies colour and can be present in two forms or two alleles as we call them: One allele specifies colour colour present, in dominant fashion, and a second allele which specifies colour absent, in recessive fashion.

The second gene specifies barring pattern, which again is present in two forms or alleles: One for normal 9 bars with bar 1 and 9 dark which is recessive, the second allele for 9 bars with bar 1, 5 and 9 dark (the Heckel gene).

Now for the gene 2 to work, in other words either normal or Heckel bars, gene 1 has be of the color present form, or else no bars can be seen at all. Snow whites have the colour absent gene only, so their barring gene is just simply switched off. End of story, snow whites cannot show any bars.....?

I may be wrong about this, because I simply do not know the precise genetics, but this is how I would think it would work.

So you are not totally bonkers and way of track here, it is a little more complicated but actually it is not that complicated really.

Hope this clarifies matters a little and does not make things even less understandable.

Kind regards,

Dirk

 

Hi Prof. Thank you for your input. I know the eruption lines. To me they are the ultimate Discus. If they just werent so damn expensive. But no, I can honestly say these were not Eruptions. The price in the shop alone confirms it too, they are going for less than R150 a piece. I found them interesting not because they were great looking, rather the contrary. It did however maybe expose me to what can happen with fish in bad breeding lines. The Eruption is a truly magnificent achievement, these two I'm talking about are 2 Red turq. looking, with multiple stress bars. It could however, as you say, be a bad Leopard snakeskin that gets bought by el cheapo importers. Even so I have seen LSS go for R500 here and then they have colour coverage on less than 50% of their body. Crazy! I suppose you are right in saying that all this is so complex that it can be argued up and down. One way of getting answers is to try and do it and see for yourself where you end up. Its just such a costly exercise. . . Thanks for the chat Prof Dirk. I'm waiting to hear how your babies are doing? Regards, Marco

 

Hi there again Prof. Dirk. I have a problem which I need some advise with. One of my young Snakeskin discus has shown a general deterioration over the last couple of days. I have changed absolute nothing in the tank except for water changes as per usual. Tank temp is at a constant 29.5'C with ph at 7.2 I have a cannister filter running in which there is some Canadian peat moss. I have not added any new fish to the tank in recent weeks. Feeding is done excessively on these fish with your flakes, ox heart, granulets, blood worm live brine/daphnia. The fish use to eat very excessively at every feeding, so much so that his stomach was bulging. About a week ago I started noticing that it would, now and again go dark and tilt over on its tail, head pointing up. This behaviour became more frequent, and at this point in time the fish is constantly dark. It is however not 'black' as normal discus would go under stress. The closest explanation I can give you is that his skin appears similar to a towel that has wet patches on it, the wet patches being darker. On the fish the skin is black in patches and thd fins are clamped and black. The fish hasnt eaten in 2 days nor has it 'passed' its guts. (pooped!) I can not put a photo on unfortunately. None of the other fish exhibit any sign of stress and are eating fine. I cant find any info that resemble these symptoms. Your input will be appreciated. Thank you. Regards, Marco

 

Hi Marco,

I am sorry to hear that you are having problems but this is typical for discus, you think all is fine and do your best and then you have this sort of problem.

I need to ask a few questions to try to diagnose this problem. Were his droppings white and stringy (sulke lang string drolle, jy weet). If this was the case then you may have a case of flagellate disease here, the organism that causes hole in the head disease but from which you nowadays very rarely see symptoms on discus because the added vitamin C does help against this. I would treat this whole tank with metranidazole at 7 mg per litres. It is often the case that the other fishes show no signs of problems, but one fish does, so this is pretty typical. Why he is tilting over backward is difficult to understand and this is not typical behavior for this problem.

What is very important though is that he does start eating again. You could move the temp up to 32 C but then you must give additional aeration if you do not have enough water movement.

Kind regards,

Dirk

 

Hi Prof. Dirk. No stringy droppings whatsoever. To be honest I have tried watching him as often as possible, and absolutely no poop has been passed. I have fed live brine twice today as well as live Daphnia, but he has eating nothing! He doesnt swim much but also doesnt hide away in the corner. In all my years of discus keeping I have never seen a fish this way. 'Kidney' shaped black blotches appear on places on his body, and his skin appears 'bloated'. I'm almost starting to suspect a constipation type thing here. Is this possible? Regards, Marco

 

Hi MArco,

You must feed some bloodworm or white mosquito larvae for roughage. If you only feed flakes, bs and beefheart mixes and the fishes just simply guzzle this down they can almost get a block gut and then this can happen. Again, I recommend increasing the temp and add a heaped tablespoon of salt to help osmotic stress.

Sterkte,

Dirk

 

Thanks Prof. Dirk. I will keep trying with the bloodworm, though as yet he has shown no interest. Will add salt this morning. Thank you again. Regards, Marco