2023 Hariwake, Beni Kikokuryu, Kujaku spawn

[Matt24]

Here's a quick update, with more details to come. Last night at about 10 pm, I added a female to the spawning tub where two males had been for a couple of days. Today they started spawning at about 1 pm. I moved them out after seven hours, changed quite a bit of the water, and did a single Broad Spectrum Disease Treatment to hopefully prevent fungus on unfertilized eggs.

This is a repeat of the same group as the 2021 spawn, https://www.koiphen.com/forums/showt...u-Kujaku-spawn . That was a successful test of spawning very mature koi. They've grown a little more and aged two years

• The Doitsu Hariwake female is 14 years old and 30".
• The Beni Kikokuryu male is 16 years old and 26".
• The Doitsu Kujaku male is 16 years old and 26".

EDIT: I should have added these photos earlier, but here are the oyagoi, so you can see what these fry came from.

[spkennyva]

Congrats Matt! Looking forward to seeing how to one works out. Your results from 2021 were really nice, so you have the bar set pretty high.

You made it sound so easy... I've got a group that's been together for many days and still nothing...

[Matt24]

Congrats Matt! Looking forward to seeing how to one works out. Your results from 2021 were really nice, so you have the bar set pretty high.

You made it sound so easy... I've got a group that's been together for many days and still nothing...

Ha! Thanks! Well I sure can't take credit for that! They were just ready. Maybe it helps to have an instigator. When I put these 3 in a spawn back in 2012 https://www.koiphen.com/forums/showt...tsu-Spawn-2012 , for a few days, I did not have the stout bodied Beni Kikokuryu in the mix. But when the hariwake would not lay her eggs I finally added the Beni Kikokuryu to the mix, thinking it was a second female. But as I discovered then, he "... was not a second female as I had thought, but a male, and the spawning instigator at that. Hey, whatever works." He was pushing the female for a while before the other males joined.

I used basically the same set up as other recent years ... 500 gal tub filled to ~350 gal, four 8'-10' nylon spawning ropes, 3 around the sides and one wrapped around a pipe weighted to the bottom. After 48 hours, I switched out the 500 GPH pump with a 300 GPH to help reduce the number of fry that get sucked into the pump. I also wrapped the pumps cage with a double layer of cheeze-cloth, though I am not sure how much that helps.

With 66 F water, I can see lots of eyes after 2 days, and you can see some even in this poor photo. I am pleased that it seems like a high fertility rate. I'd guess over 75%. For now, the BSDT seems to have reduced the amount of fungus I normally see. This is the first time I have tried that on the eggs.



Here are some photos from the action.

[Orlando]

Great to see you back, looking forward to your progress.

[spkennyva]

Hi Matt, Nice update.

Do you use the standard or a reduced dosage of BSDT? Some years I've used it and other years not, so I'm really unsure if it actually helps. However, one of the best hatch rates I ever had was when I did treat, but not certain of the causality.

[Matt24]

Hi Matt, Nice update.

Do you use the standard or a reduced dosage of BSDT? Some years I've used it and other years not, so I'm really unsure if it actually helps. However, one of the best hatch rates I ever had was when I did treat, but not certain of the causality.

I used a single regular BSDT dose, as Angie mentioned in her thread. I didn't do the series of three doses over 3 days. I wondered if it would "turn my spawn ropes blue" ... sounds like a song, but it didn't.

I'm not sure I recall if BSDT tends to knock back some of the aquatic vegetation. If so, that may be a drawback, affecting some of their food supply. Sounds like it must have gone well when you did it. I will say there was a lot less fungus than usual. Normally the ropes are covered in thick fuzz by hatching time, so much that I worry if any eggs would live. But usually I get great numbers of fry anyway.

At 9 AM today, I saw that I could lightly fluff one of the spawning rope's "pom-poms" and see a couple of fry swim out. So the first ones hatched in only about 68 hours from the time the egg-laying began. That's faster than I expected, being that the water temperatures have been in the ~66-69 F range over the last 3 days. By this afternoon, when I would fluff one, a couple of dozen fry would come out.

I starting putting in a little yeast for food, though they probably are not eating it yet, just to be safe.

I hope your oyagoi will get to it here soon. I know sometimes mine have taken several days before spawning, or taken so long that I gave up and brought in the "B Team".

I've done a couple of major water changes using water from my main pond. Ammonia is currently very low, but I am occasionally adding some Fritz ACCR to bind it.

[Matt24]

At 9 am Saturday, about 24 hours after I first saw a couple of hatched fry, the water was a little cloudy. I tested the ammonia 0.1 and added a little Fritz ACCR to bind it.

I decided to give it a little more time to make sure hatching was done. I went out to run some errands, when I came back in the afternoon, the water was cloudier. I removed the spawning ropes and dipped out some of the eggs from the bottom.

At 7 pm, I tested the ammonia ... YIKES!!! It was bright green! The brightness did not really match too well with the dull colors on the testing card, but I can only guess that it had spiked to well above 1.0, maybe 2.0. So I immediately added lots of Fritz, started a big water change, flushed the filter and started dipping out more eggs and kept it up until late that night and then most of the next day.

Now the water is clear, and the huge majority of the eggs are gone. Ammonia is 0.3 and bound. And there are still many thousands of fry (whew!) ... almost all light colored, mostly yellow for now.

[Matt24]

For the record, this spawn occured from 1 pm to 8 pm on a warm, partly cloudy day with ambient temperature ~85 F and barometric pressure 29.88 and steady. It was 4 days after a full moon. Water was 68 F.

I always move my adults to a ~0.20% salt bath for about 3 hours before putting them back into the main pond. In 2021, I moved them to the salt bath after 5 hours of spawning. Things were rowdy in that tub, and I had to move the Beni Kikokuryu out after just an hour. I later saw that she laid several hundred more eggs in that salt bath. Now in 2023 I did the same thing, but let them spawn 7 hours first. Even though they were still going when I removed them, she must have been done, because she did not lay any eggs in the salt bath, and things were much calmer. I only heard maybe 3 bangs, and I left them in for a good 2.5 hours before I removed them due to a storm moving in. So for this group at least the egg laying time is between 5 & 7 hours.

[Orlando]

Interesting information Matt, my Shiro spawn was about two days after the full moon and during day hours, the Goshiki was an entire day cycle and that probably had to do with the hatch rate being so high. Let's see how your numbers go ��

[Matt24]

... the Goshiki was an entire day cycle and that probably had to do with the hatch rate being so high. ...

Please correct me if I am misunderstanding. I gather that you mean the Goshiki took their time and spawned for an entire day.

That reminds me of an odd flock spawn a long time ago with three egg-laying sessions over a week. We had a small female and 4 large males in a pond with rocks on the shelf along the sides. After she laid some eggs, they were beating her up too much. She ducked into a little cave behind the rocks that the males could not fit into. They searched the pond in vain for her. After about 3 days, she came out and laid some more eggs and then went back to the cave when it got too rough. About 3 days later, she came out again and finished up, and she was fine after that.

[Orlando]

I introduced them to the vat during the evening but didn't start spawning until I had to go to work so they were left to finish when I returned took them out to the salt bath and back to their respective tanks they went.

[Matt24]

Here is a sample of them at 4 days after hatching, mostly light colored, but some seem a little dark. I'm currently feeding 2 tablespoons of yeast over a day and am increasing the powdered pellets, now at 3 tablespoons. Looks like the filter is handling what little remains of the decaying eggs, gradually reducing ammonia 0.25. It has cooled off, with the water now 61 F.

[Angie Jones]

Matt, I think it looks like you've got a good percentage there that will turn dark. Maybe 50/50. With these parent koi is that a good thing or a bad thing?

[Matt24]

Matt, I think it looks like you've got a good percentage there that will turn dark. Maybe 50/50. With these parent koi is that a good thing or a bad thing?

If that happens, it may be good. I know some beni kikokuryu spawners like the way the dark ones develop. Of course I only have one in this spawn. Some kujaku may look dark early on also. Looking back at my 2021 thread https://www.koiphen.com/forums/showt...u-Kujaku-spawn for this same group of oyagoi, I saw were I commented that after they all looked yellow very early on, by two weeks a very small number had developed a black spot on the head, and an even smaller number had black spots going down their back to the tail. In the end, I had some beni kikokuryu, kikokuryu, and kujaku in the mix that I liked.

[Matt24]

Following along the my 2021 experience dealing with such a large number of fry, now 8 days past hatching, I've increased feeding over the day up to 2 tablespoons of yeast and 5 tablespoons of pulverized pellets. I am now using a net with very small, but not tiny holes to sift the pulverized pellets. So lots of small granules pass through, along with the fine powder. But the weather has cooled further, with water 57 F as of 11 am Saturday. Despite their large numbers, they are smaller that typical for this age and have not been eating all of their food, as I can see some food lying around, and the water is a bit cloudy. Ammonia has risen from 0.25 to 0.4. I continue to add Fritz and will likely do some netting of the bottom to clean up some. Looking them over, they have some slight variation in color and appear to be straight. So deformities have yet to show up.

[Matt24]

I netted out some of the gunk off the bottom using the method described above to avoid losing many fry. After one of the gunk dumps, here was what was left in the ice chest. This very small fraction of the fry gives an idea of the numbers. Zooming in some may help.

[Orlando]

Wow! That's awesome and the size is pretty good for 8 days looking forward to their progress.

[Matt24]

Thanks Orlando. They need some warmer temps soon. After Sunday night, the lows should be above 60 F.

After running adult koi pellets through the coffee grinder, below are the 3 different sizes of food sifted out by using these 3 different sizes of nets.

The net with the largest sized holes is also good for netting out tobi without getting the little fry when they are small. When they get a little bigger, I use an adult koi net with a little larger holes for separating the tobi.

[Angie Jones]

Following along the my 2021 experience dealing with such a large number of fry, now 8 days past hatching, I've increased feeding over the day up to 2 tablespoons of yeast and 5 tablespoons of pulverized pellets.

Matt, are you putting this mixture in a squirt bottle with water and squirting it into the fry tank?

[Matt24]

Matt, are you putting this mixture in a squirt bottle with water and squirting it into the fry tank?

Yes, with pond water. In this case, it is an old plastic syrup bottle.