Sterbai breeding question

Boeboe · Post by **Boeboe** » 22 Mar 2007, 21:05

For about 12 days ago, after I came back from a fish auction here in Denmark, my Sterbai had spawned.
I collected about 85 eggs and put them into a flowing tank with an airstone. I use a little bit medicin against fungus, then I dont loose many eggs.
The spawning percent were about 90%, and thats fairly.
The eggs hatched allready after 4 days, much earlier that last time.
I do have some of the same problems like the other breeders here, some loose of fry in the early dayes. At this time I belive I have lost about 15%, but it seems to be my problem during feeding too much.
I change all the water in the flowing tank every day, actually I use 2 tanks, and take a clean one and put the fry over in it, thats easy, I think. Just use a bit of an airtube to move them over. Now I'm feeding with fresh hatched brinechimp, and some malculated pills, and that seems to be a good mix, I just still have to remember, not to feed too much.
Last time, I had a spawn, I raised about 175 out of 225 eggs.
But it's really great to hear about others breed, steeling some ideas can be the result,

Kind regards
Boerge Bech Jensen

NEONCORY · Post by **NEONCORY** » 23 Mar 2007, 02:09

Hi Boeboe,

Can you share the more detail of the tank set up with us since you have success raising them?

1. How many is your breeding group?
2. And what size for breeding tank and water parameter(like temp, ph and dh)?
3. And what size tank do you use to raise frys and how young(eggs, frys with egg sack, free-swimming.,etc)do they go into that size tanks?
4. And how often do you feed?

Also what is malculated pills? I don't think I am familiar with that.

Yes, it is always helpful to hear from someone done it already which you are trying to do. So we would appreciate to hear the details from you. Especially me.

BTW, I did harvest 30 more eggs this evening. 10 on the glass, 7 in the spawning mop and 13 on the leaves of Java Ferns.

Boeboe · Post by **Boeboe** » 23 Mar 2007, 13:35

Hi Neoncory

My breeding group is 7 Sterbai's, 4 females, and 3 males.
My breeding tank is a 63 liters tank, with very fine gravel. The temp is around 25 degrees celcius, and the ph nearby normal, 7. I don't know exactly the dh, I'm so lucky that I can use the tapwater directly.
The size I begin with, as a hatching tank, and the first week as fry is not more than 1-1.5 liter (around a half a gallon). I just put the eggs in the small tank as soon as I collect the eggs, sometimes several times a day, and sometimes for 2 days, not more that this. There I use a few drops of medicine against fungus, but then I have to change a lot of water at the time the eggs is hatching, else there will die a lot of fry. I normally begin to feed at the third day, not later, because else some of the fry will starve. Just be carefull not to overfeed.
The first days, after feeding, I change the water completely with water from the breeding tank, and have another small tank, so I can clean the used one totally. After about 5 days feeding, I go down to one waterchange daily. after about 2 weeks, I change the fry tank to one a little bigger, about 3 liters, a little more than 1 gallon, and use this until the place becom too small, then I just put them into a normal size tank, 45 - 63 liters.
I believe, I didn't explained me too well, with the "malculated pills", thats because English is my second language. What i ment here was crushed catfish pills, do you know then, what I mean??
As soon as the fry is big enough to eat bloodworm, in pieces, I feed with that too.

I believe, that 1 female spawn about 70 - 80 eggs, but I didn't see it actually last time.
My breeding Sterbai is 3 years old by now.

Kind regards
Børge Bech Jensen

apistomaster · Post by **apistomaster** » 23 Mar 2007, 15:48

I have now had some of my own tr sterbai spawn at less than one year old so I can cofirm they they do mature early. I imagine their fertility increses with further maturation.

NEONCORY · Post by **NEONCORY** » 23 Mar 2007, 17:39

Hi Boeboe,

Thanks for the details, I appreciate you taking time to describe. It is very helpful that this is my first time around my Sterbais spawned. I know my group are so young. They are like teenagers that barely matured. So I think it usually 20~25 eggs per female and when I get ~50~ I suspect 2 females are involved. I believe I have 3 females and 2 males. And it seems some eggs are not fertlized so I think 1 male may need further maturing to do.
The eggs hatch in 2 1/2 ~ 3days since they are kept in higher temperature than yours. I keep my group in around 82F(around 28C).
I usually collect eggs several hours after they were layed. So far they always lay eggs in late morning to early afternoon and I collect them in late afternoon to evening. And put in the small container like

perware and pin it at the top edge of the tank with air tube. And keep them and feed them for week or so. I do change 90% water before each feeding. Of course, use the water from the parents tank. I did finally set up the small tank(I believe 4~5 gallon with sponge filter) with sand and few plants with few hiding place. And I put some 1~2 weeks old Sterbai frys with Panda frys and some Cherry shrimps and small ramshorn snails. The tank is only set up for few days but I used everything from another tank so it is matured.(sponge filter, water, plants and sands). I am try to keep this tank around 75F since my adult Pandas are living in cooler temperature. Beside I am planning to put the Melanotaneas frys also in same tank and they are born in the same water as Pandas. If I set up another small tank eventually, I will seperate Sterbai frys from other two and adjust temperature to one cooler and the other warmer same as their parents tank.
So far I don't see no dead fry so I think it would be ok. I will change little water every other day or so. I am feeding some walterworms, vinegar eels and fine mixture of dry foods. I think I have less worry of over feeding that I have snails and shrimps I am hoping take care of left over. And more live food so it takes longer to foul water.
However this is still a learning and experiencing for me. Hopefully it works well.
And I will move them to bigger tank when they become 1/2" TL and 1/4" depth/thickness or get too crowdy from the number of the frys since I am planning to put more frys once they reach to week ~ 2 weeks old.

And yes I got what you mean. You are feeding crushed catfish pellets/discs.

Anyway, I'll catch you later with some updates.

NEONCORY · Post by **NEONCORY** » 23 Mar 2007, 17:54

apistomaster wrote:I have now had some of my own tr sterbai spawn at less than one year old so I can cofirm they they do mature early. I imagine their fertility increses with further maturation.

Yes Larry, I also do imagine their fertility rate and size of spawn would increase as they mature.
Although I never be sure of how old are my Sterbais since I didn't grew them but I suspect they must be around year old. They may well be younger. Once I grew some eggs to 3/4"~1" TL I can guess how old they are better. That was about the size I got them in last November which is 5 months ago. And I started collect eggs in biginning of this month which is about 4 month from when I got them from the store.
Anyway, I will know if I grow these frys to adulthood and they start their own families. I sure hope so. Then I will know how long it takes for them to be matured enough to make eggs.

apistomaster · Post by **apistomaster** » 23 Mar 2007, 18:17

Hi neoncory,

It is only now that I have raised my own C. sterbai from egg to young adult that could say with any certainty that they can be bred at just under one year of age.

Breeding the less common Corys is a recent venture for me so I am still very much in the early phase of my learning curve.

Previously I only had practical experience with Corydoras aeneus, reg, albino and C. paleatus.

The wild Corydoras (and I will include sterbai) are proving to be an enriching experience as an aquarist.
It is always fun, to me, to learn about the breeding of new species.

I am noticing many defects in the TR C.sterbai which is making me plan on aquiring some wild stock this year. I notice that foreshortened spines are a frequent defect and is present in the new albino sterbai as well. The problems with Corydoras panda are another Cory I want to get beyond the farmed fish which are the most available by getting wild fish to work with.

NEONCORY · Post by **NEONCORY** » 27 Mar 2007, 05:33

Hi apistomaster,

Yeah, I kind of figure my Sterbais are pretty young.
And I don't have much Cory raising experience either. Panda was my first and Sterbai the 2nd and now got Melanotanias but I think their first batch of eggs were duds. It's been a week and none hatching. It is a shame since there were more than 100. Anyway, hope next time they will hatch.

I , too think that tank bred fish need to be infused with some new blood every few generation if not more.
I would like to get some wild caught also if they are available locally. Since I am not crazy about mail order.
But it would be more like I have to settle for next best. I would get more fish to increase the gene pool instead of growing the off-spring up to join the breeding group.

Also I have been admiring the Albino Sterbai. If I can manage to get some of those, I would breed with regular to strength. I believe this is what they call "back cross"? Anyway, they are pretty nifty fish. But I can see they are just like any other albino that they are more fragile than the regular.

apistomaster · Post by **apistomaster** » 27 Mar 2007, 05:52

It is just a matter of personal taste but I don't see the need for another variety of Albino Corys. Seen one albino Cory seen 'em all.

NEONCORY · Post by **NEONCORY** » 28 Mar 2007, 00:26

I forgot to post that I did collect 10 eggs on Friday afternoon/evening and 14 eggs on Sunday afternoon/evening.
And I just collected 45 eggs(10 on the glass, 15 in the spawning mop , 1 in the Java moss and 19 on the leaves of Java Fern.)
And I saw not only 1 but 2 T's at the same time. So I guess 2 females were laying eggs and 2nd male get lucky also sometime.

NEONCORY · Post by **NEONCORY** » 29 Mar 2007, 00:32

I collected 14 more eggs(2 in the Java Moss, 3 in the spawning mop and 9 on the leaves of Java Fern). I think these came from the 3rd female since I saw 2 females were making eggs yesterday.

NEONCORY · Post by **NEONCORY** » 30 Mar 2007, 03:10

Collected 24 more eggs this evening. I'm pretty sure they came from the 1st female since 12 eggs were on the glass, 3 on the spawning mop and 6 on the leaves of Java Fern and 3 more on the leaf of Anubias.
And most of the eggs were placed higher part of the tank.

NEONCORY · Post by **NEONCORY** » 31 Mar 2007, 05:50

I was suprised to count 73 eggs(68 eggs in the spawning mop, 2 in the Java moss, 2 on the Anubias leaf and 1 on the side of the container). Now I have no idea if 2 or 3 females work on the egg production. I think they know the Easter is coming and crank up the production.

NEONCORY · Post by **NEONCORY** » 01 Apr 2007, 02:21

I collected 52 more eggs. 12 on the glass, 1 on the plastic of powerhead outlet, 4 on the leaves of Anubias, 21 in the spawning mop and 14 on the leaves of Java Ferns.
I know I did 50~60% water change yesterday but they are really cranking up the production for the Easter.

Oh and as usual they make eggs after the breakfast around the nooner.

cartouche · Post by **cartouche** » 01 Apr 2007, 13:36

When my first group of sterbai (5 males+3 females) started their first spawning season 5 years ago, they usually produced few eggs throughout the week, but once in 1-2 weeks they gave about 60 eggs. The second spawning season was much richer; they produced about 100 eggs every 14-16 days.

NEONCORY · Post by **NEONCORY** » 01 Apr 2007, 17:30

Hi cartouche,

That is very interesting info. I must say now I know what to expect next few years. I am sure I will keep them. Since you have some 5 years experience under your belt, now I have few questions.

1. I'm pretty sure but did the hatch rate and fry survival rate improve as the year goes by?

2. Did the eggs become bigger as the parents grew?

3. After 5 years, do they slow down(getting too old) yet?

4. When do they lay eggs? Mine seems almost always in the morning/early afternoon until today.

This morning I got up and go do some water change for the little containers which hold eggs and I notice there are 2 eggs on the Java moss and 1 on the leaf of Java Fern. I know it wasn't there when I collected eggs yesterday evening.
So those eggs had to be made sometime between 6P.M ~7A.M. I wonder if the male convince after dinner or after dark or early morning.

I did not remove everything to see if there are more. Since I imagine I had to do it anyway this evening.

cartouche · Post by **cartouche** » 02 Apr 2007, 00:27

NEONCORY wrote:Hi cartouche,

That is very interesting info. I must say now I know what to expect next few years. I am sure I will keep them. Since you have some 5 years experience under your belt, now I have few questions.

1. I'm pretty sure but did the hatch rate and fry survival rate improve as the year goes by?

I think it's always the same. In fact, this group has an almost miraculous fertility rate; once I experienced that only one out of ca. 90 eggs was infertile. Their "children" are somewhat less successful, but still, the fertility rate is very high, about 80-90%. Remember that when a female spawns for the first time in the beginning of a spawning period, the fertility rate is very low, ca. 50% and sometimes even lower. I think it is due to the overripeness of the eggs.

2. Did the eggs become bigger as the parents grew?

I don't observe anything like that.

3. After 5 years, do they slow down(getting too old) yet?

I observe that the pauses between spawnings are longer and longer, and the number of eggs per spawn increases. As I said, during the first spawning period, they gave me 60 eggs a week maximally. During the second spawning period, they spawned every 14-16 days with 100 or more eggs. Last year the pauses lasted 3 weeks and the number of eggs could be as high as ca. 170 pieces. This year they spawn every 3-4 weeks and gave me 100-150 eggs maximally, sometimes within 2-3 succesive days. It seems that the three females now spawn separately, because I can get 130 eggs from one spawning, and shortly after, say after 5 days, I get another 90 eggs and after another few days 50 eggs. Then a long break follows. It is very improbable that one female could produce such a number of eggs within such a short time. Now I start adding earthworms to their usual menu, because I think it's an important component that elevates the number of eggs. It seems that it already started to work, because I got over 200 eggs from another breeding group of sterbai today.

4. When do they lay eggs? Mine seems almost always in the morning/early afternoon until today.

They start in the morning and continue till the evening. Sometimes they continue even the next day, until the females are empty.

This morning I got up and go do some water change for the little containers which hold eggs and I notice there are 2 eggs on the Java moss and 1 on the leaf of Java Fern. I know it wasn't there when I collected eggs yesterday evening.
So those eggs had to be made sometime between 6P.M ~7A.M. I wonder if the male convince after dinner or after dark or early morning. I did not remove everything to see if there are more. Since I imagine I had to do it anyway this evening.

NEONCORY · Post by **NEONCORY** » 02 Apr 2007, 02:39

Thanks cartouche for all the info. I appreciate you took time to answer them. I don't know how my group do from 5 years or 3 months from now. But for now, they are laying eggs everyday and I'm try not to complain although finding and collecting them can be difficult. I may need to simplify the set up.

Anyway, I collected 32 eggs this evening. 15 in the spawning mop, 15 on the leaves of Java Fern, 1 on the glass and 1 onthe leaf of Anubias.

NEONCORY · Post by **NEONCORY** » 03 Apr 2007, 04:18

I am so surprised

to collect 101 eggs today. I don't know this came from 2 or 3 females. I sure don't think it came from 1 female.
Anyway, there were 10 eggs on the glass, 9 on the outside of the container which I keep some eggs from few days ago, 68 in the spawning mop, 2 on the leaf of Anubias and 12 on the leaves of Java Fern.
If I could raise even half the eggs to young Sterbais, I would have 100+ in 3~4 months.
Another question would be, how long is this last. Since this is my first month getting eggs from Sterbais let alone the first year and season.
I better set some tank(s) up. I guess it's gonna be a busy April for me.

cartouche · Post by **cartouche** » 03 Apr 2007, 14:39

I don't know if in other Sterbais it is the same, but the spawning period in my fish lasts about 3 months - or somewhat longer than 3 months -, and then they have a pause lasting approximately 5,5 months.

NEONCORY · Post by **NEONCORY** » 03 Apr 2007, 18:17

Hi cartouche,

I don't know how my group would do. Since they only started beginning of last month for first time in their life. It started every other day but now it is everyday since last week. I imagine regular water change is helping since every day I take about 1G from their tank so I can use it to change fry tank with it and tap it up with cooler new water.
But frankly, I am not sure if I get any eggs from them today after the big batch from yesterday. Although they are swimming all over already.

I am also readying your thread about the problem with raising frys. I am not saying this would work for you not to mention I have only been doing such a short time and I only have Pandas and Sterbais frys.

But I am almost certain that I have less frys loss since I start using method below. Well at least, raising Sterbai frys.
At first I tried to hatch without any fungucide then tried methlene blue for first day( I did wanted to use as less chemical as possible. Beside they hatch in about 3 days in the temperature they are kept.) Anyway just few days ago, I obtained the bottle call "Pimafix" from Aquarium Phamaceutical and it say All Natural so I decide to give it a try.
Also I decide that all the talk of bad bacteria and slimy coat on the bottom of tank and such on fry dying thread. I decide to keep my frys as soon as they hatch in container with the sands from the parents tank and it seems I have much less fry loss. Still I can't declare that I found the cure since I just start trying. And variation of species. Need more time to validate. But so far, I must say I have less fry loss than when I kept on bare bottom for them to absorb egg sack.
And you probably know this I move them to small tank about week after free-swimming. And that small tank have some hiding place, I really don't know how many are growing. I put about 20 Pandas and 20 Sterbais in last 2 weeks. And I am about to set another little tank since I have about 180 eggs which I am hoping at least 120 hacth in next 2~3 days.
And I don't have anything bigger than 4 weeks old since they started spawning in beginning of last month.
And I know you have big success with your Sterbais and I don't know this would work for other Cory frys but I thought I want you to know. And maybe give it a try and see. But like I said, I am not 100% sold yet for this since I just started and don't have enough data to back it up yet.
Anyway, I hope you can find the cure for your problem.

cartouche · Post by **cartouche** » 03 Apr 2007, 23:24

Hmm, an interesting suggestion... But it would make me big problems. I tried it once with sand, and I don't want to repeat it anymore. The fry can't be seen, the food falls into the sand...

NEONCORY · Post by **NEONCORY** » 04 Apr 2007, 21:08

cartouche wrote:Hmm, an interesting suggestion... But it would make me big problems. I tried it once with sand, and I don't want to repeat it anymore. The fry can't be seen, the food falls into the sand...

Hey cartouche,

It sounds like you used the gravels and not sands. Because the sands I use is really fine grain and I can see the frys if they are not hiding underneath of something. Right now, most of them are under the sponge filter. I should get the one stay little above the ground.
And for the food, I think my snails and Chrry Red Shrimps should take care of it if there are any left over. For now, I am almost feeding nothing but vinegar eels and walterworms(just like microworms but suppose to be smaller). And little really finely grinded dry food once in a while. This is all after they are week after free-swimming.
Before then, I hatch them keep in the small container like 4" x 4" x 3"D tapperware with airline. And put thin layer of sands from the parents tank(I think the surface of sands should have some beneficial bacteria and such, probably bad ones also. But some reason, flat bottom either container or tank hover more bad kind of bacteria. Or maybe just it is not good for the frys to contact with the slimy coat from the bottom all the time. Especially when they are still not move much while absorbing the egg sacks) Of course, this is purely the speculation but I do have much less casuality of frys while they are absorbing egg sack. Compare to I kept them in the container without sands in it. I used to lose 1 frys everyday about 3~4 total out of 12 while they are laying on the bottom of container. Now I lose 1 out of 12 and 11 become free swimming. Of course, I do change water everyday with parents tank water. And before they totally lose their egg sack, I put little walterworms for them just in case some fry develope faster and need some food. I keep them in this small container for about a week after they become free swimming. Then move to 4~5 G tank with sponge filter some plants, sands, snails and Cherry Red Shrimps.
I am in process of setting another tank like that for next batches. I am new to this so I don't know how many frys can go in for how long in how big the tank but I'll try to move them up to bigger tank or split them in 2 tank or something as time goes on.

Like I mentioned my oldest is about 4 weeks old. And I don't have long record to back it up but it sure looks I have more free swimmer if I kept the wigglers in the container with thin layer of sands in it. And it seems that is the time I lost most of the frys so far. Then again, I only have some todpoles and they are not much of catfish yet.

I don't know if anyone would try this but so far I will keep raising my wigglers and older with sands. It seems work for me better than the bare bottom.

Maybe you take dozen or so wiggler in small container and try with sands. Although I don't know it makes any difference between new sands and matured sands from the established tank. Something tells me it will. So you might not be able to try immediately if you don't have fine sands in any of your tank.

Anyway, this is what I do. We'll see how many I have in 3~4 months from now. Hopefully 100+.

Fortunately I see them making more eggs today after the day off yesterday.

NEONCORY · Post by **NEONCORY** » 05 Apr 2007, 07:10

Yeah, collected 31 more eggs. 2 on the glass 2 on the plastic outlet from the powerhead, 14 in the spawning mop and 13 on the leaves of Java Fern.

apistomaster · Post by **apistomaster** » 05 Apr 2007, 08:53

neon,

I know it is exciting to have our fish spawn but is there a point to post a running egg count?

Can you imagine what it would be like, to just take one of many species of fish I raise, Corydoras sterbai. If I had posted a daily count of how many eggs I had each day until I reached the ~8000 eggs the breeding group laid over a 3 month period?

Just be pleased that they are spawning. When you hit a problem or question not covered in the stickeys post it. If you discover a better way of doing something, post it.

Daily reports of the results of egg counts might be more usefully kept in a log book rather than posting every one you find.

Just something to think about.

NEONCORY · Post by **NEONCORY** » 06 Apr 2007, 18:04

apistomaster wrote:neon,

I know it is exciting to have our fish spawn but is there a point to post a running egg count?

Can you imagine what it would be like, to just take one of many species of fish I raise, Corydoras sterbai. If I had posted a daily count of how many eggs I had each day until I reached the ~8000 eggs the breeding group laid over a 3 month period?

Just be pleased that they are spawning. When you hit a problem or question not covered in the stickeys post it. If you discover a better way of doing something, post it.

Daily reports of the results of egg counts might be more usefully kept in a log book rather than posting every one you find.

Just something to think about.

OK. I thought someone out there who just start breeding Sterbai or who is planning to do that might find useful. How many eggs and how often they lay eggs and such.
But if everybody who come to this forum find my egg report is not necessary like you. Then, I would reduce my posts. And I will just post only when something important happened.

apistomaster · Post by **apistomaster** » 06 Apr 2007, 21:59

Once they start spawning and as long as you continue to give them good care, a group will spawn everyday for months on end until you either separate the sexes or they take a rest break to build up a new egg supply and rest their reproduction system. Then it will start over again and so on for the next 5 to 7 years.
The only thing that changes is how many eggs are found everyday. Oh well, what the heck, whose counting?

NEONCORY · Post by **NEONCORY** » 08 Apr 2007, 17:58

Yesterday finally I moved my Sterbais to another tank which I shuffled around to open it. I was thinking to do that since I noticed the bubbly look on the silicone few weeks ago.
After drain the water half way and moved the parents to new tank and collect some eggs. And after that drain some more water and I noticed there are some survivors on the bottom. So catch those and put them in the fry tank.
I just hope they will like the new home. It is pretty same since I move the filters and decoration from the tank they moved from except it has much lighter sands.
Anyway, I am glad this is done since I was worried about the leak for a while.
And I do still count the eggs while I am collecting them. I guess I am always curious about how many they lay eggs.

apistomaster · Post by **apistomaster** » 08 Apr 2007, 18:25

Glad you repaired the leak. It is always good to know that you won't have a disaster.

It id useful to know how many eggs you start with so you can calculate the % of survival so you can gage the fertility rate. The % of good eggs goes up as the breeders mature.