PROBLEMS WITH DYING FRY

[Coryologist]

Hello Frank,
I only know you from what I have read in your posts and I can tell when someone is a an accomplished aquarist and that I can learn from the experiences they choose to share.

I have found what you have shared to be very useful and on target. Therefore I have appreciated what I gained from what you have shared.

I am also an accomplished aquarist but I do not have the same depth of experience in the art of raising wild Corydoras as you. My expertise is deeper in other areas.

I quite understand your position on whether one is respected or not is of no consequence. Some people do care and are even pleased to learn they have helped others.

I agree that an aquarium is never an accurate simulation of a fish's biotope. We do what we can and if it is near enough sometimes our fish reproduce.
That is the reward to a breeder of challenging fish.

That's all very nice, Larry. Nicely stated and truly appreciated. But if that's true - why did you stick it up my butt with such a nasty, condescending post? Why couldn't you post this instead of the other? Is it that your basic nature IS to be confrontational and argumentative? That's just not my cup of tea, so I can't and won't get into a p*ssing match with you. Too old, sick and tired. Sorry. If you were looking for blood sport, you engaged the wrong guy. Life's too short.

As far as my expertise: I've said this before and I'll say it again for the last time. Here's the secret to my having spawnied 25 different specie of Cory in 7 short years. I put them in water, I feed them, I do "normal" water changes and I hope. That's it. I have no tips, tricks, secrets or anything else to offer. Now, you may regard that as sarcastic as it probably does not jibe with your belief system. I can't help you with that. Reality is what it is.

These fish have spawned without my help for hundreds of millions of years. I would never be so humanly arrogant to assume that I have some "power" over a living creature. When they want to spawn, they spawn. I let them live their lives with as little interference from me as possible.

If I was so good at this, perhaps my colony of C. condiscipulus might have spawned after a 7 year wait. They haven't.

Yours in peace! - Frank

P.S. Must remember to correct the spelling on this pic.

[Coryman]

Rather than critique others comments, which is not going to get any of us anywhere, I will put my perspective on the whole thing. We have a species, C. duplicareus, which it appears both cartough and apistomaster are experiencing the same dramatic fry loss after a relatively long period of success.
After a lot of to and fro-ing there have been no real answers and the one question I asked cartouch, which was not answered was, have you had a post-mortem done on the dead fry. Seeing that this is someone who is breeding for profit I cannot understand why it has not been done. I for one would have had this done as soon as I could see no solution. If fry are dying before they even start eating then to me the problem has nothing to do with food and the only way to find out why they died is by examination of the bodies by an expert. Once the cause of death is determined only then can a possible solution be found, until then it's just guess work.

I am breeding this species in a very simple way, I call it my natural way because my stock are in a planted tank, mainly Java moss and fern, the adults are left in the tank and on average I am taking out 20 -25 sellable young every month. I am not a clinical breeder (Plain tanks, no substrate or furnishings), it's not the way I like to see or breed my fish.

If a post-mortem is ever done on the dead fry I would be very interested in reading the report.

Ian

[apistomaster]

Hello Frank,
I actually had my fry problems with sterbai and the duplicareous have only spawned twice and the eggs did not hatch. A similar situation exists with C-121 which resembles duplicareous.
I am equipped with a good microscope and if I get fry with problems I will be placing them under the 'scope to see what there may be to see. I will try to take photomicrographs of anything that shows up.

The sterbai losses were frustrating but I still produced nearly 1000 so I pretty much am done with them for now.
I can only hold and sell so many fish at a time to meet my customer demands.

I am just applying my efforts on the former species and the recently aquired weitzmani.

[cartouche]

The ESHA test, having only been tried once, reveals nothing that can be concluded as fact. It could be nothing more than coincidence. I would like to see this repeated a few more times, before I would give it any creedence, whatsoever. Additionally, I would only consider it a fact when I can personally duplicate the results in my own fish room.

Please accept my missive in the spirit with which it is proffered. I am not trying to be confrontational, nor, argumentative. Just trying to find a valid solution to a problem that I believe will take much more research, by different individuals to see if the results can be duplicated. Until then, the results have no scientific validity and can only be classified as anecdotal.

A single drop of anything, being a magic cure, to my way of thinking, just doesn't hold water (no pun intended). Would be vey interested in seeing who is able to duplicate the results that cartouche has achieved on a regular basis.

I for one would be interested in participating in such a group experiment. Any other volunteers???

Regards,

Frank

It was not a single test. From the first bunch of duplicareus fry, 13 out of 20 survived. Then I tried the same procedure in Corydoras trilineatus. Usually they were all dead after mere 3 days. But after the application of ESHA, the whole group of ca. 12 pieces survived. Then another 20 duplicareus hatched on Monday, I used the same procedure with ESHA, and except one (that was probably some degenerated piece), all are still alive and I just started to feed them. On Thursday, I had another 5 pieces of duplicareus fry and I placed them in a little container with a drop of methylene blue - and today - after mere 3 days - all are already dead.



What about a post-mortem investigation, I didn't think about it until recently, when I started to suspect that there may be some problems with bacterial or other microbiological beasts. I always thought that there was something wrong with the water. However, I couldn't imagine, how an investigation on such small pieces of fry would be possible. I already had problems with a rare disease 3 years ago and I delivered the dead fry (about 1-1,5 cm long) to the veterinary laboratory. And they complained that it is complicated to make an investigation in such a small fry. And what about a freshly hatched fry that is 4 mm long!

[apistomaster]

If bacteria are the primary cause of fish disease there are few viable options that are worth trying. Most of those diseases are beyond much practical efforts by aquarists to cure. Mysterious fry deaths by bacteria is an even more dismal prospect.

It does not mean that microscopic examination may not help provide some more information to consider.
At low power it would be interesting to see what the assumed causitive organism is doing to the external development of the larvae.

To view the bacteria is more complicated. The affecedt sample larvae can be crushed along with stains to get an idea of the general types of bacteria and the same done to healthy larvae from a different source spawn and tank could be used as a crude control.
It may then be possible to see if there are quantitatively more of particular forms of bacteria on the sample of the sick larvae than are found on the control healthy larvae sujected to identical prep.
It is a very crude analysis if I may be so bold to call it that. If nothing else it is something new to see under the microscope for me. Who know's what will be seen and hopefully photographed? If the smashed sick larvae is a mass of bacteria compared to a smashed healthy larvae that information is a small stet towards understanding what is going on.
To use the oil immersion lens crushing the the sample larvae is necessary for optical reasons like depth of field.
Maybe it will lead to experimenting with high intensity UV sterilization pre and post spawning is enough to minimize the problem. I am just speculating.
It won't hurt(except the sampled larvae) just to look and it won't make things worse.

I have had this problem using the natural method I think Frank says he preferred and it has happened in the more "sterile" bare bottom method of spawning tank set ups for me. I should have tried this while I was in my sterbai production phase and having the troubles.

All this is just hobbyist level microbiology and microscopy. No pretense on my part that an amazing discovery will be made.

I would not expect a treatment specific to be gleaned from the exercise but it would just add another perspective. I am never very hopeful that I can do much about bacterial problems except exercise better hygiene and husbandry to try to prevent conditions conducive to adverse bacterial growth

[NEONCORY]

Hey cartouche,

Are they any progress of your fry raising problem?

[cartouche]

Hey cartouche,

Are they any progress of your fry raising problem?

The ESHA 2000 doesn't seem to be a miraculous stuff, but at least, ca. 50% duplicareus fry survive. However, it works excellently in C. trilineatus, where all the hatched fry survive. (But I still have problems with feeding.)

[NEONCORY]

Well at least it improve to 50%, it sure beat the 0~10%. It just sounds like C. Duplicareus is really sensitive delicate cory.(I never kept them so I don't have any experience with them.)
Anyway, you just need to keep trying. Maybe it may improve still. Who knows it may need little more or less of ESHA 2000 or length of time., etc.

[cartouche]

Well at least it improve to 50%, it sure beat the 0~10%. It just sounds like C. Duplicareus is really sensitive delicate cory.(I never kept them so I don't have any experience with them.)
Anyway, you just need to keep trying. Maybe it may improve still. Who knows it may need little more or less of ESHA 2000 or length of time., etc.

I tried to increase the concentration of ESHA up to the highest dose recommended for adult fish, but the result was practically the same.

I think the problem lies in the presence of infusoria in water. And it seems that recently it manifests even in larger fry. During the last weeks I started to experience big loses of fry (duplicareus, sterbai) after I moved them from little containers to big tanks too early, and I fed them with decapsulated artemia. I noticed that the little fish tried to escape from the bottom and hung everywhere on the filter or glass. From some reason, they didn't want to stay in the lower part of the tank. They also didn't eat well and after mere two days in the tank, they suddenly started to die on a mass scale. I lost 30 little Sterbai last week and I didn't understand why. Then I placed another 40 sterbai there and one day later, during a regular water change, I let them for 30 minutes in a small volume of water. When I started to fill the tank with new water, I observed that some of the sterbai behave strangely and after the tank was full, I found 5 dead sterbai on the bottom. Almost all remaining sterbai hung on the tank's sides.

I remember that one breeder told me about exactly the same behaviour of his fry, when they were allegedly attacked by "predatory infusoria". I don't know why it appeared just now; I have never had any such problems since 1997, when I started to breed Corys. It is simply another of many new curious problems that I encounter during the last year. In any case, the fry seem to be immune to the problems, when they are at least 14 days old. I must thus keep them in small containers for the whole first 14 days.