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elduderino
05-07-2009, 04:34 PM
Hi,

Just had my first-ever koi spawn. So much to learn. I do have a specific question, however. The fry finally started to hatch last night (checked every couple of hours 'till i slept). So I assumed there'd be many many of them in the morning, but that isn't the case. I'd say there's a couple dozen swimming around now in the QT/Fry tank. It's about 100 gallons. Anyhow, I found that there were several dead fry in the tank. Much more so than live ones. Is this normal? Are ammonia levels too high? The water isn't filtered, but I am running two air stones through it starting this afternoon.

Also, at what point do I remove the spawning media (in this case, hyacinths and string algae)? It's been six days since the first eggs were laid. Water temp is around 70.

Thanks for any advice!

stephen
05-07-2009, 04:42 PM
Hi,

Just had my first-ever koi spawn. So much to learn. I do have a specific question, however. The fry finally started to hatch last night (checked every couple of hours 'till i slept). So I assumed there'd be many many of them in the morning, but that isn't the case. I'd say there's a couple dozen swimming around now in the QT/Fry tank. It's about 100 gallons. Anyhow, I found that there were several dead fry in the tank. Much more so than live ones. Is this normal? Are ammonia levels too high? The water isn't filtered, but I am running two air stones through it starting this afternoon.

Also, at what point do I remove the spawning media (in this case, hyacinths and string algae)? It's been six days since the first eggs were laid. Water temp is around 70.

Thanks for any advice!

I would remove the spawning media now. I would also do a large water change making sure that the pH & water temp doesn't vary much. They are so fragile at this stage.

tnthat
05-07-2009, 04:47 PM
We use a constant flow through system when spawnning. High ammonia and temp. swings can cause high death rates.

elduderino
05-07-2009, 04:56 PM
thanks for the replies...it's 100 degrees here in socal today...that certainly isn't helping. I'll remove the media and put in some fresh water from the main pond right now.

tnthat
05-07-2009, 05:03 PM
Do not drop the temps. too quickly.

stephen
05-07-2009, 05:07 PM
Also test the pH from the tap and the pond. It may be very different and can kill the fry quickly. I speak from experience. I lost 1000's a few years ago because of this. After most all died, I checked the pH's:rolleyes: It shocked them.

CHICHI
05-07-2009, 05:15 PM
Even when Params are fine there is usually a mass mortality phase when rearing fry :eek1: less are lost though when Params are spot on ..

Super Kindai
05-07-2009, 08:11 PM
Hi,

Just had my first-ever koi spawn. So much to learn. I do have a specific question, however. The fry finally started to hatch last night (checked every couple of hours 'till i slept). So I assumed there'd be many many of them in the morning, but that isn't the case. I'd say there's a couple dozen swimming around now in the QT/Fry tank. It's about 100 gallons. Anyhow, I found that there were several dead fry in the tank. Much more so than live ones. Is this normal? Are ammonia levels too high? The water isn't filtered, but I am running two air stones through it starting this afternoon.

Also, at what point do I remove the spawning media (in this case, hyacinths and string algae)? It's been six days since the first eggs were laid. Water temp is around 70.
Thanks for any advice!

strong aeration is not recommend especially for fry.

around 70 is fine but 76 - 78 is preferable. if possible, maintain water temperature by using a heater.

Super Kindai
05-07-2009, 08:22 PM
thanks for the replies...it's 100 degrees here in socal today...that certainly isn't helping. I'll remove the media and put in some fresh water from the main pond right now.

:no:......fry do not have immunity from a disease. tapwater is safe.

elduderino
05-07-2009, 08:35 PM
so dechlor + tap water? Hm...I did a 50% water change, but water from the main pond, not tap. Will keep that in mind.

There are fewer and fewer survivors. Just did a check, and had to search for 5 minutes till I found one that was alive. Unlucky for them.

All spawning media is now removed, even though there were still plenty of eggs on them. Water temp is 80F, and regrettably I have no ph readings. Working on that...

As we're nearing the 24 hour mark post-hatching, should I introduce food as is normally recommended after this purpose? And coming back to my original question, is it normal for this many fry to die? Surely not?

Regardless, i'll be better prepared for next time...I think the string algae as a [circumstantial] spawning media isn't a good choice...too messy, and my theory is that some of the fry died just getting lost in it. I'll be stoked if I can get a couple survivors! Any!

If anyone is interested, the spawn was a combination of a doitsu sanke female (24"), male doitsu sanke, (22") two kohakus (m, f, ~20"), and a 14" female doitsu shushui mutt who i didn't think was old enough to spawn.

Super Kindai
05-07-2009, 09:12 PM
so dechlor + tap water? Hm...I did a 50% water change, but water from the main pond, not tap. Will keep that in mind.

There are fewer and fewer survivors. Just did a check, and had to search for 5 minutes till I found one that was alive. Unlucky for them.

All spawning media is now removed, even though there were still plenty of eggs on them. Water temp is 80F, and regrettably I have no ph readings. Working on that...

As we're nearing the 24 hour mark post-hatching, should I introduce food as is normally recommended after this purpose? And coming back to my original question, is it normal for this many fry to die? Surely not?

Regardless, i'll be better prepared for next time...I think the string algae as a [circumstantial] spawning media isn't a good choice...too messy, and my theory is that some of the fry died just getting lost in it. I'll be stoked if I can get a couple survivors! Any!

If anyone is interested, the spawn was a combination of a doitsu sanke female (24"), male doitsu sanke, (22") two kohakus (m, f, ~20"), and a 14" female doitsu shushui mutt who i didn't think was old enough to spawn.

Yes, dechlor + tap water.

you do not need to feeding any food during first 3 days or so at all because they get nutrition from it's egg sack.
As far as I know and our experiences, it is not normal for that many fry to die. actually, fry is strong especially first a few days prior to feeding. So, it should be something wrong with the water, probably ammonia???

If you still have good eggs on spawning media, you may put them in any container(s) with new fresh dechlor + tap water..... I think that you still have a chance to get health fry......a lot.

elduderino
05-10-2009, 01:01 PM
Just an update:

We have survivors! Dozens of them. The combination of better water quality and their increasing size has made them easier to spot. On a whim, I put the hyacinths back in, and I think it's vastly improved the water quality and given the fry a bit more security. To see the fry I just push a bunch of hyacinths aside, and can see several swimming toward the plant.

Also, in the last few days, the bubbles at the surface of the water have gone from thick and slow, to small and crisp. Did a ph check, and we're at ~ 7.8. I've been putting a few drops of reducer in per day to keep the levels steady. Have not done a water change since the initial setup. Will do some dechlor + tap water later in the day. The temperature difference between low and high is 20 degrees currently, ranging from 64 to 84 degrees. A bit steep, but so far, it's okay. Will post a photo of the fish when they're big enough for my digi cam to get them! 'Till then, this is a shot of their home.
http://i38.photobucket.com/albums/e128/AramDellalian/DSCN9195.jpg

And to go back to the original topic....Fry Mortality Rate....in this case it happened in droves. Higher than 90%, I'd say, but has stabilized considerably in the subsequent days.

Super Kindai
05-10-2009, 04:20 PM
:clap:

Doitu Sanke is generally not so strong compare to other primitive variety koi such as Chagoi, etc.
There is a simple but definite theory. Good refined type offspring are weak, then bad primitive offspring are strong.
Now, the fry are in a survival race each other. therefore, in order to increase survival chances particularly for good potential fry.....

If I were you, I would ..........

1) Use a heater, set around 75 F, in order to avoid the current huge gap between low and high in a day.

2) Do a water change around 20%+ everyday, (....depend on a food amount and a water condition though.)

3) Add more water in the pool to gain total water volume which helps to maintain stability of a water condition.

4) Try to get rid of waste on bottom of the pool. waste or leftover food begin to decay in that's higher water temperature within 24 hours.

5) Get rid of all hyacinths......................:rolleyes:

elduderino
05-10-2009, 05:17 PM
Done!

http://i38.photobucket.com/albums/e128/AramDellalian/DSCN9196.jpg

Went out and got a ammonia test kit. Main pond tested at 0ppm. The fry pond.....4ppm! Surprised there were still some alive with those ammonia levels!

Super Kindai: I've done all on your list except the the heater. I doubled the water volume with 50/50 pond/tap water. Ammonia is much lower, at about 1ppm right now. Got as much of the debris out as I could. It's tough because the fry get scooped up with the leaves/branches. Will slowly do it by hand. I have some dried fry food, but haven't yet fed. There are plenty of small larvae-looking creatures in the pond. They are much smaller than the fry, and I hope the fry munch on them for a while.

Super Kindai
05-10-2009, 09:09 PM
That was fast!
Wow, ammonia was dangerous zone, wasn't it........:eek1:

I think that Ammonia 1ppm / ph 7.8 is a safe zone right now but not ideal. In addition to that, (as we know) a barometer of small volume water tends to change quickly. so, continuous observation of the water condition is strongly recommended.

the debris can be carefully removed by the siphon method. and plenty of small larvae-looking creatures are great food source for the fry. If it is daphnia http://en.wikipedia.org/wiki/Daphnia then perfect..:D:

expat
05-11-2009, 04:40 PM
That was fast!
Wow, ammonia was dangerous zone, wasn't it........:eek1:

I think that Ammonia 1ppm / ph 7.8 is a safe zone right now but not ideal. In addition to that, (as we know) a barometer of small volume water tends to change quickly. so, continuous observation of the water condition is strongly recommended.

the debris can be carefully removed by the siphon method. and plenty of small larvae-looking creatures are great food source for the fry. If it is daphnia http://en.wikipedia.org/wiki/Daphnia then perfect..:D:
For my info, i understood that daphnia could be dangerous to small fry, maybe it depends on the type of daphnia?

Super Kindai
05-11-2009, 07:35 PM
For my info, i understood that daphnia could be dangerous to small fry, maybe it depends on the type of daphnia?
You have an interesting info..
There was an old Japanese koi dealer in my area and I remember that , it was about 15 years ago or so, he said one of his customer who bred koi killed all hatched fry because a guy fed wrong kind of daphnia which have something like a spine...........
I have never been heard or read before or since. but there maybe the different type of daphnia??

What I know is that it's said new born fry can not eat mature daphnia because sizewise too big for fry. So, new born fry can only eat new born tiny size daphnia.:D:

CHICHI
05-11-2009, 07:45 PM
You have an interesting info..
There was an old Japanese koi dealer in my area and I remember that , it was about 15 years ago or so, he said one of his customer who bred koi killed all hatched fry because a guy fed wrong kind of daphnia which have something like a spine...........
I have never been heard or read before or since. but there maybe the different type of daphnia??

What I know is that it's said new born fry can not eat mature daphnia because sizewise too big for fry. So, new born fry can only eat new born tiny size daphnia.:D:

In a Natural "Green" Water" Pond environment the very Numbers of Fry outweigh the local Biota/Protozoa :yes: this keeps the numbers of survivors in check due to the "weak" being constantly Predated upon and wheedled out ..

Super Kindai
05-12-2009, 12:02 AM
In a Natural "Green" Water" Pond environment the very Numbers of Fry outweigh the local Biota/Protozoa :yes: this keeps the numbers of survivors in check due to the "weak" being constantly Predated upon and wheedled out ..
It makes a good sense to me, CHIHCI. That's why professional koi breeders in Japan prepare daphnia of explosive large quantity in fry mud ponds prior to the breeding in order to keep "weak ones = (possibly) Good ones".:yes:

elduderino
05-27-2009, 01:44 AM
Hey! Here are some shots of the fry. One month old today. Plenty of tobies. During the water change, I saw one of the tobies with one of his brothers in his mouth! Gah. I'd say there are at least 100. Some are well under 1/2", some are 1 1/4"+, and the median size is between the two. I'd say when some are 4 times bigger than others, it's tobie cull time. Did a big water change today and cleaned out their kiddie pool tank, and added an aquarium filter (photos of that tomorrow).

http://i38.photobucket.com/albums/e128/AramDellalian/DSCN9343.jpg
http://i38.photobucket.com/albums/e128/AramDellalian/DSCN9340.jpg

Super Kindai: Any reason why I can't add hyacinths at this point? Params are great: ammonia 0, Nitrite 0, ph 7.8, and temps range from 60-75. Moved the kiddie pool to an area with less debris, but the tradeoff is more sunlight, so I think the hyacinths might help this.

Super Kindai
05-28-2009, 02:16 AM
Super Kindai: Any reason why I can't add hyacinths at this point? Params are great: ammonia 0, Nitrite 0, ph 7.8, and temps range from 60-75. Moved the kiddie pool to an area with less debris, but the tradeoff is more sunlight, so I think the hyacinths might help this.
I am glad to see many of the one month old fry/baby.....:cool:

Regarding to the hyacinths, I think it will be a good idea to add hyacinths in the pool at this point.
the reason why I recommended to remove hyacinths at that time was because an idea of "not to provide any hiding places" in a growing pond of fry especially in an early stage is commonly known among Japanese hobbyists who have an interest for breeding fry/baby.
It's called "Ishiko"in Japanese which means a stone child (fry) that eat only algae on stone instead of regular food around because of shyness.
As a result of that, these Ishiko are not only staying small size but also turn to be deformed mouth, face shape, and unhealthy.
In addition to that, shy ones are considered to have more chance to be good koi in future than wild, insensitive type -tobies- fry.
Hyacinths (or any kind of plants) are hiding places as well a stone/ rock for these potentially good sensitive fry....;)

expat
05-28-2009, 05:22 PM
You have an interesting info..
There was an old Japanese koi dealer in my area and I remember that , it was about 15 years ago or so, he said one of his customer who bred koi killed all hatched fry because a guy fed wrong kind of daphnia which have something like a spine...........
I have never been heard or read before or since. but there maybe the different type of daphnia??

What I know is that it's said new born fry can not eat mature daphnia because sizewise too big for fry. So, new born fry can only eat new born tiny size daphnia.:D:
Several web sites I looked at to purchase daphnia had more than one type, some were quite large.

Super Kindai
05-28-2009, 06:09 PM
Several web sites I looked at to purchase daphnia had more than one type, some were quite large.
It seems like there are about 450 different kinds of daphnia in the world...:eek1:

http://www.cnas.missouristate.edu/zooplankton/alphabetical%20listing.htm

http://cyclot.hp.infoseek.co.jp/mijinko/mijitopx.html

elduderino
06-06-2009, 01:10 PM
Babies are doing well. I transported 18 tobies to a separate 25 gallon tub. The remaining fish grew almost overnight once the bigger brothers were removed. The kiddie pool has more water volume than the 25, and so, has more nutrients for them to eat. All else equal, the tobies will grow at a slower rate than their smaller brothers.

So.

Can I put the tobies back into the main fry pond once they've evened out a bit? Sounds like an obvious solution, but just wanted to make sure.

I'm feeding them a mix of algae wafers and frozen bloodworms at the moment. Going on 6 weeks old!

elduderino
06-14-2009, 12:43 AM
Photo from today's water change:

http://farm4.static.flickr.com/3303/3624317674_212dc629c9_o.jpg

counted 251 fry!

EricT
06-14-2009, 12:51 AM
i see a couple i like..... WOW!!!!! 251 FRY!!!!!!!!!!!!!!! i only have like 20 fry.