Infertile eggs

du ma · Post by **du ma** » 01 Jun 2006, 06:57

My group of 6 aldofoi spawn several times but the eggs were never fertilized. I am pretty sure there are males in the group but theyre not fertilizing the eggs properly. Can anyone who bred these give me some tips on spawning them please?

They are housed in a 10 gallon tank with driftwood and lots of plants. Temperature is at 77 and the pH is in the high 6 or low 7. Lights are on for about 10 hrs a day.

Oh! They are feeding on live Calif. black worms, algae wafers, and carnivore pellets.

MatsP · Post by **MatsP** » 01 Jun 2006, 11:00

I can't answer your specific question, but before Ian says it, I'd like to point out that Algae wafers aren't really for Cory's. They are suitable for plecos that require some vegetable/fibre. There are other wafers with more meaty and less vegetable/fibre content that are better food for Cory's.

--
Mats

martijn · Post by **martijn** » 01 Jun 2006, 14:05

- What do you do with the eggs, after the spawning?
- How sure are you of the gender of the fishes?

@ MatsP: the algea wafers are compensated, i read, with live Calif. black worms and carnivore pellets.

Bye Martijn

cartouche · Post by **cartouche** » 01 Jun 2006, 14:32

I can tell you that rearing Duplicareus is not an easy task at all. The fish spawn very easily, but

1/ Eggs are very prone to fungusing
2/ They need a special water to hatch (each breeder says something else; I use a chemistry that another breeder can't use because the eggs wouldn't hatch

)
3) Hatched larvae are very sensitive to changes of water chemistry; it may even happen that despite the eggs hatch excellently, the larvae may suffer from some osmotic problems (e.g. too high pH).
4/ The overall fertilization rate is very low, usually about 60-70%, but when the eggs are too many, it may be as low as mere 40%

Remember that when the fish begin to spawn, eggs are often not fertile (probably because the female gets rid of too old eggs), so I wouldn't make a drama of it so far. But if you observe that even, say 3rd or 4th spawning is not fertile, then there may be something wrong with the fish.

du ma · Post by **du ma** » 03 Jun 2006, 06:22

The eggs are laid on the plants and clay pots and I leave them as it is. I only see 3 or 4 of them but I am pretty sure that there are more hidden in the plants. This is their third or fourth attempt and I HOPE I am seeing some progress. The eggs were laid on last sunday night and two of the visible eggs haven't turned white yet. I am also seeing tiny dots inside the egg but they dont resemble anything, just random dots. Is it just decomposing?

I took a shot of it but not a very good one.

Does it look fertilized?

Also, I just threw in a longfin bristlenose in the tank for algae control. Would it be ok? ITs about an inch and a quarter.

Sorry for all the noob questions, its my first time trying to breed cories.

kim m · Post by **kim m** » 03 Jun 2006, 09:15

Yes, I think your egg look fertilized.

I've never bred C. adolfoi, but a number of other species. I have no problems what so ever with fungus on the eggs. I use pure rainwater and no chemicals at all, as I think these should de avoided at any cost. For anti-fungus, use alder cones.

Hope you can use this

cartouche · Post by **cartouche** » 03 Jun 2006, 15:43

I wouldn't be so sure about the egg, though. I would have to see it in my own eyes. Inside the infertile eggs there will appear a white point after ca. 12 hours, but some eggs may only be somewhat cloudy and the point is very indistinct, so I rather wait another few hours to be sure that I am not removing fertile eggs. But you can't wait too long, because the egg may fungus.

Fungusing is a very serious problem both in duplicareus and adolfoi. I know an experienced breeder, who just started with adolfoi and he says that he gets two pieces of fry out of 80 eggs. And I can tell you my own stories about bunches of 100 eggs, from which I got no fry at all. The problem is - quite surprisingly for me - usually in the air of the fishhouse, if it is not ventilated for a long time.

If you collect so few eggs, then the possibility to collect infertile eggs is high, so it's premature to make any conclusion from it. In any case, collecting eggs in a planted tank is not a reasonable way how to breed this species. They have only few eggs (unless you feed them very heavily) and if you can't find many of them in the tank, then you will collect few tens of fry maximally. But if I read well, you don't care about the eggs and let them in the tank. If you have a good chemistry of water, then some of them may hatch.

kim m · Post by **kim m** » 03 Jun 2006, 17:19

Fertilization rates can be good in C. duplicareus. I get 1 infertile egg out of 50-80 eggs and a 100% hatching from the rest.

sojapat · Post by **sojapat** » 03 Jun 2006, 19:08

Hi Did you check your hardness in the water ?
This does affect the fertilization on the eggs .
If the water is a little hard the eggshell to simplify is
made to thick for them to be fertilized..
Check the Gh+Kh .
It may be the problem for these?

cartouche · Post by **cartouche** » 04 Jun 2006, 00:31

Do you breed sterbai, too? I can also get one infertile egg out off 50-80. Maybe we should exchange our fish.

In any case, such a fertilization rate is simply impossible in my duplicareus. I could have such a high fertilization only if they laid 20 eggs maximally; since the time they have crossed 50, the fertilization rate is weak. Usually it even decreases, when spawning lasts more than one day. It seems that males are already tired a bit

You must have a high ratio of males to females, I think.

cartouche · Post by **cartouche** » 04 Jun 2006, 00:48

By the way, what are the parameters of your water (pH, hardness)?

kim m · Post by **kim m** » 04 Jun 2006, 03:36

I have no readings on my water, but I can take a water sample with me when I go to work tomorrow and do pH and mS/cm readings.

My sterbais are doing 50-100 eggs in a spawning (2 females, they are quite young) and I have also a 98-100% fertilization rate there.

du ma · Post by **du ma** » 04 Jun 2006, 04:37

Oh yea!!!!!!!!! They're fertilized alright. The ones I put in the net are hatching as I am typing this. What should I feed them once their yolk sacs are absorbed?

The pH is in the high 6 and I am not sure about the hardness. I dont have the kit to test the hardness. TDS is in the 300s.

kim m · Post by **kim m** » 04 Jun 2006, 17:06

Hmm...forgot my water sample... thinking does not work well when doing night shifts...

Congrats on the hatching!

Personally I use microworms for the first week or so and then add some decapsulated brine shrimp eggs. If their stonmachs turn orange, they can eat this, and then thir food consists of decapsulated brine shrinp eggs and crushes flake.

Yan · Post by **Yan** » 04 Jun 2006, 19:39

I had the same problem with C. adolfoi:
http://www.petfrd.com/forum/showthread.php?t=18002

But now it is over.
I didnâ??t do anything more then is written in the link.
For the last four-month they keep spawning every two weeks (the max amount of eggs is 113). With each spawn the percent of hatching rises. And for the less time almost 80% hatched.
I think that only now they started to mature although they are already almost two years old.

Yan

cartouche · Post by **cartouche** » 04 Jun 2006, 22:09

I have a group of 31 duplicareus in one tank. They are 1-4 years old and come from different spawnings since summer 2003, when I started with ten pieces. It was not just the best material, one female was degenerated (without barbels) and produced degenerated offspring. During the time I had to remove her from the breeding group and her unfit babies, too. The fertilization rate was quite high then, but gradually dropped, as the number of eggs increased. Until the number of fish reached 20 pieces, they usually had a 3-month's spawning period and then a 3-month's lounge. But now they have been spawning uninterruptedly since summer 2005 (probably different females in different time), many times a month, and early this year the total number of eggs easily crossed 400 pieces a month. Now it somewhat decreased - probably because some productive females took rest - , but still it is within the range 50-100 pieces a week.

Maybe some of the males are not 100% mature yet, maybe some of them are infertile, but considering the number of fish it's really not easy to say which of them are responsible for it. I think the easiest way how to solve this problem would be adding some new males into the tank, but again, it is very difficult to recognize gender in young 2,5-3 cm fish. But I will try it.

By the way, from time to time I have the same problems with eggs you reported. They get white and virtually desintegrate. I must confess that so far it is not perfectly clear to me, where the cause lies. I can use a certain developmental water, where the hatching of eggs runs perfectly for several weeks, but suddenly it stops and all eggs get white. So I must experiment with another developmental water, and several weeks after I find the best composition, the eggs get white again... It may have something to do with the fact that the chemistry of my tap and well water varies in time.

fishfarmer · Post by **fishfarmer** » 05 Jun 2006, 02:06

I also went thru various struggles with breeding and rearing Adolfi fry a few years back that I recorded in a breeding report on my web page.

http://cinci-fishfarmer.com/reports/cor ... lfiBR.html

Water hardness seemed to be key for the eggs to hatch and water depth for success in rearing the fry.

Good luck

Steve

cartouche · Post by **cartouche** » 05 Jun 2006, 18:25

Thank you for sharing your experience. But I think that my problem is not in the water depth.

I made a lot of experiments with water and it seems to me that there are two "ideal" sorts of chemistry for the development of eggs: one is a combination of harder water (7-7,5 dGH) with low pH (6,5); the second one is a combination of softer water (4-4,5 dGH) with higher pH (7,5). In theory, a water with ca. 5-6 dGH and pH 7 could work, too, but it's harder for me to mix it, so I use only the two mixes above. Surprisingly, one breeder reported that if he uses soft (ph 6,5) water, his eggs won't hatch, if hardness gets over 6 dGH.

Certainly, adolfoi is not the same like duplicareus and duplicareus bred in captivity may consist of different stocks from different localities. But that's only my theory so far.

Post by **Coryman** » 10 Jun 2006, 13:38

Just thought I would add a couple of interesting points in the C. adolfoi discussion. A very good friend of mine was probably one of, if not the first to breed these in the early 1980's and here are some of the facts he recorded.

1. His best breeding results were at temperatures in the low 80's F (84ÂºF), with around 80% fertility.
2. Hatching in 4 days and free swimming after a further 2 days.
3. He also noted that the fry were not eating and appeared to be dying of starvation, no matter what foods were given and lost something like 80% or even 90% of the first few broods. He thought that for some reason the fry did not appear to know how to eat, although it may well have been that the food they would naturally first feed on was not present. He overcame the problem by putting fry of the same age or eggs laid at the same time together, when the second species fry became free swimming and started feeding so do the adolfoi fry, it was as if by mimicking the actions of the other fry the adolfoi fry learned what was food and the losses were reduced dramatically. 85 -9% successful rearing was achieved thereafter. I followed the same pattern with great success.

Ian

Infertile eggs

Infertile eggs

Infertile eggs.

C. adolfoi