Latest Breeding Project - Dark Angels

[terrapins]

What can cause a die off?

Many factors. Foremost: water chemistry imbalance that leads to sustained stress and its underlying cause is typically due to a filter needing major attention. or undersized. Foul brine-shrimp is the foremost factor in fact if you give them brine shrimp which has a stench to it, you can almost guarantee that within the week, you'll see increasing numbers of lifeless bodies beginning to litter the bottom (unless the parents get to it first). This last one is the most common cause of die-offs in fish under dime size. Unfortunately, once they begin dropping like flies, those already affected will not respond to therapies/interventions. If anything, medications become highly toxic for them to handle and accelerate their demise. However, interventions will save those yet unaffected ones.

[catsma_97504]

While your generalities are true Ted, I believe other factors are what I've been dealing with in regards to this dark pairing.

Filtration is not an issue in this tank. I am using a 130g sponge filter in a 29g tank that holds this adult pair and a large piece of driftwood. There is a small amount of gravel in this tank that existed before I moved fish around to use this tank as a breeder, but I clean that gravel after removing the fry and when I expect the next spawning to occur. Other pairs have successfully raised offspring in this very tank, including my surprise Clowns.

The earlier spawn I posted about was lost due to water chemistry changes in my municipal water. I have natural spring water about 9 months out of the year, but late spring and most of the summer I get river water. The natural spring water is very soft (2-4 dGH, 0-3 dKH), low pH and high PO4; while the river water is moderately harder (6-8 dGH, 4-6 dKH), higher pH and contains enough Fe I don't need to dose it in my high tech tank. And, I never know when this change will occur. But when it does I always end up with fish losses. It is expected every spring and fall, but I don't know exactly when it will occur.

I suspect the drugs I have been using to treat the disease on this male is also a factor. This latest spawn developed in treated water. Who knows what kind of affect it had on the embryos or on the development of the wigglers.

As I do not experience such losses with my other pairs I also believe that genetics is playing a role. I have never worked with dark pairs before, but it is my understanding that being D/D leads to a certain degree of losses. Some of the literature I've read calls the Dark gene a lethal gene due to low survival rates. My pair is a D/D Black female and a D/+ - pb/pb - Sm/+ - St/+ Streaked Smokey Pinoy male. The male is from Mike Gibbs and is actually darker in color than the DD female. I have heard from others that this is common with Mike's dark angels. Anyway, as I should have 50% DD offspring and 50% D/+, if it is true that the Dark gene is lethal, then wouldn't it be expected to deal with such losses? I could be wrong as this is my only Dark pair I've been working with. I have another DD pairing where both are DD. I may put them in a tank and see how well their offspring do as a comparison.

But, something else that nags at me is this disease I am dealing with. It is the same flesh eating disease that killed off all my other Smokey Pinoy and all but two Blue Smokeys. I lost 10 fish from this disease and thought I had put it behind me. But this one last Pinoy had a couple of the marks showing early symptoms; and I started treatment with the Nitrofurican Green I had left over. It is helping to heal these lesions, but he is not back to full health. So, could it be that this disease is attacking the fry and killing them off early? As there are no signs of the fry the parents had to have eaten them. Why I will never know.

So, like I previously stated, I am not sure what the root cause may be, but I intend to get this male back to full health and try again. Further I will not separate the DD female as she has been exposed to this disease and I will not spread it to my other tanks.

I need to build a 55g rack so I can move out the juveniles in my 4th 29g tank and use it as another breeder. So many plans and big ideas; just not enough time or space to do it all at once.

[terrapins]

While your generalities are true Ted, I believe other factors are what I've been dealing with in regards to this dark pairing.

Yep, a general response to a general question. Best practice is to rule out fundamental/rudimentary variables/factors as the kick-off for a postmortem.
The most common cause of a die out doesn't start out directly pathologic; of course it can, but many times it is caused by environmental issues. Left unresolved, you can almost guarantee that it will trigger a die out that's much more sinister - one whose basis is now a full blown pathologic die-out. Once it escalates, the die out becomes unstoppable and can potentially cause complete mortality. Catching it while still in the environmental stage gives you way better odds of halting it almost immediately.

Filtration is not an issue in this tank. I am using a 130g sponge filter in a 29g tank that holds this adult pair and a large piece of driftwood.

While supersizing a filter is definitely the way to go if you have the space (once I start feeding brine shrimp and depending on tank population size, I add another 125G class fine pored sponge plus a box filter containing carbon and zeolite to the existing 125G class filter in place to my 29s), it isn't a means to an end. It's capacity can plummet, sometimes abruptly, because what determines its ultimate ongoing operation to support the tank's population is its state of effective capacity as time goes on. That is highly dependent on the volume of accumulted debris and maintenance state at any given point in time.

There is a small amount of gravel in this tank that existed before I moved fish around to use this tank as a breeder, but I clean that gravel after removing the fry and when I expect the next spawning to occur. Other pairs have successfully raised offspring in this very tank, including my surprise Clowns.

How big was that population compared to this prior to the die out?

The earlier spawn I posted about was lost due to water chemistry changes in my municipal water. I have natural spring water about 9 months out of the year, but late spring and most of the summer I get river water. The natural spring water is very soft (2-4 dGH, 0-3 dKH), low pH and high PO4; while the river water is moderately harder (6-8 dGH, 4-6 dKH), higher pH and contains enough Fe I don't need to dose it in my high tech tank.

It shouldn't really affect health let alone cause a die out; on the otherhand, I'd be very alarmed if my water went from a very basic range to very acid particularly if KH is as low as yours to begin with. Though you won't have to worry about Ammonia toxicity (it converts into its ionic state in pH's below 6.8) the real danger is pH crashing resulting in death by acidosis with up to 100% mortality in one instant. But I doubt that this is the cause since that would have killed the majority and you'd have very few left if at all. BTW. Here's an online German Hardness to parts-per-million converter for the above: http://www.fishtanksandponds.co.uk/c...dnesscalc.html

And, I never know when this change will occur. But when it does I always end up with fish losses. It is expected every spring and fall, but I don't know exactly when it will occur.

Doesn't your village/city send out a newsletter announcing when water maintenance will occur? (ours do, though I don't think I've ever seen any information on switching from one source to the other).

I suspect the drugs I have been using to treat the disease on this male is also a factor. This latest spawn developed in treated water. Who knows what kind of affect it had on the embryos or on the development of the wigglers.

Surely that's a possibility if you used anti-biotics not only during the embryonic stage and that would also have affected filter bacteria to compound the problem further. Also, a major effect would be on the male's fertility it may drop down to unusual levels. In addition, it may also cause an increase or the occurrences of deformities in the resulting brood.

As I do not experience such losses with my other pairs I also believe that genetics is playing a role. I have never worked with dark pairs before, but it is my understanding that being D/D leads to a certain degree of losses. Some of the literature I've read calls the Dark gene a lethal gene due to low survival rates. My pair is a D/D Black female and a D/+ - pb/pb - Sm/+ - St/+ Streaked Smokey Pinoy male......

The dark gene in of itself isn't any more deleterious than say the albino gene. On the otherhand, any recessive in double dose will affect robustness - Kois, German Blue Blushings, Sunset Blushings, Philippine Blue in double dose....etc. are all known to be less robust than genotypes without double recessives. It gets worse as double recessives in genotype pile up - the more there are, the less robust the variety will be.

But, something else that nags at me is this disease I am dealing with. It is the same flesh eating disease that killed off all my other Smokey Pinoy and all but two Blue Smokeys. I lost 10 fish from this disease and thought I had put it behind me. But this one last Pinoy had a couple of the marks showing early symptoms; and I started treatment with the Nitrofurican Green I had left over. It is helping to heal these lesions, but he is not back to full health.

The lesions may be caused by hex but open flesh is also an instant gateway to the bloodstream. I think you meant Nitrofuracin Green - a cocktail of nitrofurazone plus anti-fungal dyes (I forget what specifically, methelyn blue I think is one of them though) will surely help keep bacteria out and prevent fungus from taking hold of the lessions.
You'll need metronidazole to get rid of the flagellates.

So, could it be that this disease is attacking the fry and killing them off early?

If the underlying culprit is hex/spiro, you'll need metronidazole. And if that is indeed the case, I wouldn't be surprised if that what's causing your die-out.

As there are no signs of the fry the parents had to have eaten them. Why I will never know.

You know, I should have asked you this for starters - if you have a full blown die out, there should be evidence you'll see a an amount of bodies, dying or dead underneath the sponge filter where the adults can't get at them. On the otherhand, if you're not seeing any it is also plausible that the parent pair may be culling them - a phenomenon whose triggers are not fully understood. The fact is, if you have a pair parent their brood, you can almost guarantee that the final headcount you end up with at weaning time can be as much less than what you started sometimes up to half to 3/4's of the original count.

The "dwindling phenomena" (that's what I call it) is greatly exacerbated if at the end of the day turn the tank's lights off and leave it in pitch black darkness. When that occurs, the parent pair will snap at anything touching them - including their fry.

So, like I previously stated, I am not sure what the root cause may be, but I intend to get this male back to full health and try again. Further I will not separate the DD female as she has been exposed to this disease and I will not spread it to my other tanks.

Behavioral imprinting would have already taken place so pulling the parent pair now won't interfere with it. In fact, I recommend it because of the stress that nurturing behavior places on a sick parent. It may not show while they have fry but its effect on the adults' health will be plain once you pull them out. Depending on the size of the adults, you may be able to get away with a 10g. tank - its temporary anyway. In addition, if you haven't seen dead bodies at the bottom, weaning them should prove once and for all whether you are indeed experience a die-out as opposed to parental culling.

I need to build a 55g rack so I can move out the juveniles in my 4th 29g tank and use it as another breeder. So many plans and big ideas; just not enough time or space to do it all at once.

I can both empathize and sympathize with you on this count - it's a perpetual problem for many of us who breed angels. LOL

[catsma_97504]

[QUOTE=terrapins;1306]

While supersizing a filter is definitely the way to go if you have the space (once I start feeding brine shrimp and depending on tank population size, I add another 125G class fine pored sponge plus a box filter containing carbon and zeolite to the existing 125G class filter in place to my 29s), it isn't a means to an end. It's capacity can plummet, sometimes abruptly, because what determines its ultimate ongoing operation to support the tank's population is its state of effective capacity as time goes on. That is highly dependent on the volume of accumulted debris and maintenance state at any given point in time.

Very true. A filter's capability is dependent on its ability to pass water through the materials. While this normally isn't an issue for me, it is time to give that sponge a big squeeze.

How big was that population compared to this prior to the die out?

This was a small spawn. Again, developing in a medicated tank, and the male being sick, didn't surprise me. However, I'd estimate 100-150 fry. There was no die out. They were there and then they weren't. All at once which is why I suspect the parent ate them.

Here's an online German Hardness to parts-per-million converter for the above: http://www.fishtanksandponds.co.uk/c...dnesscalc.html

The calculator isn't really necessary, but is handy. All you have to do is multiply the degree aka drop count by 19.7 to convert to PPM.

Doesn't your village/city send out a newsletter announcing when water maintenance will occur? (ours do, though I don't think I've ever seen any information on switching from one source to the other).

There is no notice or warning to this change. It happens based on water demand. I have called our Water Commissioner and spoken with him on multiple occasions. In fact he was shocked I was aware of the change; and he was the one who told me about the two water sources and their differences chemically. And at one point he asked for my address, and knew immediately that I was in fact dealing with changes to source water.

Surely that's a possibility if you used anti-biotics not only during the embryonic stage and that would also have affected filter bacteria to compound the problem further. Also, a major effect would be on the male's fertility it may drop down to unusual levels. In addition, it may also cause an increase or the occurrences of deformities in the resulting brood.

Completely agree. Male is not back to 100% full health, so not surprising to experience such issues.

The dark gene in of itself isn't any more deleterious than say the albino gene. On the otherhand, any recessive in double dose will affect robustness - Kois, German Blue Blushings, Sunset Blushings, Philippine Blue in double dose....etc. are all known to be less robust than genotypes without double recessives. It gets worse as double recessives in genotype pile up - the more there are, the less robust the variety will be.

What I find interesting is that not only are recessive fish genetically is that this same lack of thriving spawns occurs with the Dark gene, which is not recessive. Not sure if it is fully dominant or a partial dominant as I've seen some fish with the Zebra gene that do not appear dark to my eye. But that is a completely different topic.

The lesions may be caused by hex but open flesh is also an instant gateway to the bloodstream. I think you meant Nitrofuracin Green - a cocktail of nitrofurazone plus anti-fungal dyes (I forget what specifically, methelyn blue I think is one of them though) will surely help keep bacteria out and prevent fungus from taking hold of the lessions.

Yes, you are correct. I didn't spell it correctly originally. Notrofucacin Green contains a blend of nitrofurazone, sulfathiazole sodium, methylene blue and sodium chloride. When I first experienced issues with killed 10 adult angels, I contacted National Fish Pharmacy. They recommended a treatment plan of 4 weeks of Nitrofuracin Green followed by 2 weeks of Metronidazole. And as this disease is returning I have followed the same suggested treatment plan.

You'll need metronidazole to get rid of the flagellates.

If the underlying culprit is hex/spiro, you'll need metronidazole. And if that is indeed the case, I wouldn't be surprised if that what's causing your die-out.

Yes, I am aware of this. I am now feeding metro laced flakes to this pair now that the lesions have mostly healed. This too is a thought I have had regarding the loss of the spawn.

You know, I should have asked you this for starters - if you have a full blown die out, there should be evidence you'll see a an amount of bodies, dying or dead underneath the sponge filter where the adults can't get at them. On the otherhand, if you're not seeing any it is also plausible that the parent pair may be culling them - a phenomenon whose triggers are not fully understood. The fact is, if you have a pair parent their brood, you can almost guarantee that the final headcount you end up with at weaning time can be as much less than what you started sometimes up to half to 3/4's of the original count.

The "dwindling phenomena" (that's what I call it) is greatly exacerbated if at the end of the day turn the tank's lights off and leave it in pitch black darkness. When that occurs, the parent pair will snap at anything touching them - including their fry.

Yes, this phenomena is mind boggling. And is exactly what has occurred. No dead bodies. I even moved the driftwood and picked up the sponge filter when I last cleaned their tank and it only contained the expected small amount of detritus that was lifted out. All I can say is that the 2-day old fry existed at night when I fed them; and even watched to make sure they were eating. Turned out the lights for the night, but as there is a street light right outside my house, with the curtains open the room is not in complete darkness ever. This pair has successfully raised fry in the past with this same practice.

Behavioral imprinting would have already taken place so pulling the parent pair now won't interfere with it. In fact, I recommend it because of the stress that nurturing behavior places on a sick parent. It may not show while they have fry but its effect on the adults' health will be plain once you pull them out. Depending on the size of the adults, you may be able to get away with a 10g. tank - its temporary anyway. In addition, if you haven't seen dead bodies at the bottom, weaning them should prove once and for all whether you are indeed experience a die-out as opposed to parental culling.

This raises another question. How long does it take to imprint? When can fry be separated with the imprint and hopefully grow into parent raising adults themselves? I do understand the stress of parenting, but had no luck with 2 spawns I recently pulled from another pair as well as this one. Apparently I am not a good surrogate parent to angelfish.


Thank you for taking the time to put your thoughts down. Always appreciate input from others as that is how advancement in this hobby occurs for me

[terrapins]

While this normally isn't an issue for me, it is time to give that sponge a big squeeze.

I've been asked many times by my customers, associates, and even people who happened to acquire my name from a friend of a friend and in some instances from people who's seen my auctions about how to stop a die off. I say the same thing - do 2 90% waterchange 8 hrs apart then 24hrs later, if die-outs persist especially when it occurs a couple of hours or so subsequent to feeding and it was observed that the dead bodies have full bellies and mouth open, perform sponge maintenance and add another filter - preferably cycled from a tank without sick fish.

If the issue are toxicity spikes, this will halt it immediately assuming of course the fish do not show any signs of disease such as loss of body mass or emaciation (like their bellies were pinched at the perimeter), darkening of fish that appear to be bobbing at the bottom (not "belly sliding" but wiggling in place with little to and fro movement).

The calculator isn't really necessary, but is handy. All you have to do is multiply the degree aka drop count by 19.7 to convert to PPM.

I meant that for those wondering what those units meant. If we don't have it already, we should have a reference section with conversion or unit calculators.

There is no notice or warning to this change. It happens based on water demand. I have called our Water Commissioner and spoken with him on multiple occasions. In fact he was shocked I was aware of the change; and he was the one who told me about the two water sources and their differences chemically. And at one point he asked for my address, and knew immediately that I was in fact dealing with changes to source water.

I was just looking at our latest village newletter and though it has a water related maintenance schedule, source switching isn't addressed, just to confirm (just like in your case, our locale does shift sources).

What I find interesting is that not only are recessive fish genetically is that this same lack of thriving spawns occurs with the Dark gene, which is not recessive. Not sure if it is fully dominant or a partial dominant as I've seen some fish with the Zebra gene that do not appear dark to my eye. But that is a completely different topic.

Not sure what you meant initially until after I re-read what I wrote. DUH! now the above make perfect sense. So, to clarify what I wanted to relay:

There are 2 characteristics that I was writing about:

1. The reputed deleteriousness of the dark gene relative to the albino gene.

2. Recessive genes in double dose are what's definitely deleterious.

Point #2 has nothing to do with point #1 but the way I wrote it made it read like an implication that the dark gene's reputed deleteriousness is because it's a recessive - which it is not. In retrospect, I should have never written Point# 2 since at most, it is a tangent to the topic. Thanks for catching that verbiage, I could have really confused readers greatly (if I haven't already).

When I first experienced issues with killed 10 adult angels, I contacted National Fish Pharmacy.

Holy cow! 10 adults? That is painful, sorry to hear about that. How long ago did this occur?

They recommended a treatment plan of 4 weeks of Nitrofuracin Green followed by 2 weeks of Metronidazole.

Here's an alternative therapy cycle which I've used successfully:

I would do metronidazole for 5 days and at the same time dose with with Nitrofuracin. In addition, I would also dope some flakes with metronidazole since the anti-biotic is immiscible in water, in fact you can't even emulsify it - they drop like rocks straight to the bottom. Normally, I'd recommend increasing the temperature to 86F to 90F to increase metronidazoles efficacy. But because you're dealing with very small fish, it's difficult to assess whether their rate of respiration normal or due to a pathologic or parasitic cause (very young fish pump their gill plates at a much quicker rate than larger fish). In addition, the symptoms of a bacterial related illness is not readily observable via the typical outward indicators. Both cases is cause for foregoing the generally recommended increase in temperature; instead, lower it to 78F. Now because most pre-doped flakes are formulated for larger fish, there's a possibility of overdosage. So limit the amount that you'd normally feed them but stick to the recommended schedule.

Yes, this phenomena is mind boggling. And is exactly what has occurred. No dead bodies. I even moved the driftwood and picked up the sponge filter when I last cleaned their tank and it only contained the expected small amount of detritus that was lifted out. All I can say is that the 2-day old fry existed at night when I fed them; and even watched to make sure they were eating. Turned out the lights for the night, but as there is a street light right outside my house, with the curtains open the room is not in complete darkness ever. This pair has successfully raised fry in the past with this same practice.

The light outside may not be enough since angels aren't nocturnal fish and so it's key to keep the light on.

This raises another question. How long does it take to imprint? When can fry be separated with the imprint and hopefully grow into parent raising adults themselves?

[QUOTE=catsma_97504;1308] [QUOTE=catsma_97504;1308]

I'm not an ethologist so I've really never performed tests to pin point how early imprinting occurs. However, suffice to say that once they've learned the basics such as responding to fin clicks that their parents perform to "call" them to their side or better yet, once they're visibly alarmed by danger - such as staying out of the way of a siphon - once visible, in my book the imprinting process has already taken place. The actual association of the angelfish parent-offspring bond and the consequent behaviors arising from it is a topic that I have yet to see as a white-paper on the internet. I suspect that it occurs in phases. One thing's certain, unparented spawns have no clue what a siphon is and do not associate it with danger as early as those that are parented.

I do understand the stress of parenting, but had no luck with 2 spawns I recently pulled from another pair as well as this one. Apparently I am not a good surrogate parent to angelfish.

To be honest, I hate pulling eggs because I hate watching the obvious panic that the parent pair goes thru (the female more than the male in most cases) after I steal the eggs. In addition, I feel that pulled spawns means more work for me and especially come time to do maintenance since they get in the way.

[Danburns]

To be honest, I hate pulling eggs because I hate watching the obvious panic that the parent pair goes thru (the female more than the male in most cases) after I steal the eggs. In addition, I feel that pulled spawns means more work for me and especially come time to do maintenance since they get in the way.

I also will only pull eggs as a last resort. The solution I've found to save the spawn and help minimize parental anxiety is to use one of the hang-on Marina Breeder boxes. I place it on the breeder tank a couple of days before I expect a spawn and start the water circulating through the box. Once the pair have spawned I slowly move the slate, making sure that both parents watch the move. I place the slate into the breeder box with the eggs facing the tank so that the parents can still see the eggs. If the parents do not lose sight of the eggs they adjust readily without panic. The parents still try to tend the eggs through the glass. I use no antifungal treatments and rarely need to remove any bad eggs. If there are eggs to be removed I try to do that as fast as I can and once the work is done I turn the slate back so that the eggs are once again facing the pair. I leave the box on the tank for a few days after all are freeswimming. Soon the pair start paying less and less attention to the babies and I then place a fresh slate in the breeder tank and remove the Marina hang-on box.


I do not have one of the hatching jars from AngelsPlus, but I would imagine it would work just as well if left in the tank with parents.


Maybe an option to ponder.

Dan

I'm thinking of trying this process with newly formed pairs on their first couple of spawns as a great many of our pairs eat their first spawn or two. On occasion we have a pair take to parent raising right off the bat but most do not. With Discus I have a plastic cage that I slip over the breeding cone to protect the eggs, but I have not tried it with Angelfish. The cage allows the Discus pair to fan the eggs yet not allow them close enough to eat them.