Amblydoras nauticus spawned

[bekateen]

Well done!

I've noticed I get a better egg hatch rate when eggs are prevented from touching each other.
I use the fine mesh under egg crate concept with one individual egg in each compartment, stacked several layers high with gentle down flow. Boost the dissolved oxygen with an airstone in a corner, raise temperate for faster hatch and can use UV if fungus becomes a concern. For the screen, I use a fiberglass midge mesh product. Superglue to fasten.

Alternatively another setup suggestion:
I use open top plastic drinking cups with an electronic soldier iron to create small holes around the sides, 3 cm off the bottom so you can pick up a cup without it completely draining out. These are useful for individual hatching and then raising fish that would normally eat each other. It's easy to feed through the open top and you can buy a thousand cups relatively cheaply that neatly stack when not used. The plastic tote trays can stack vertically as well.

Very interesting! Thanks for the photo. It helps me understand much better!

Cheers, Eric

[bekateen]

Update on the fry and eggs.

Most of the eggs from the second spawn turned milky white within 24 hours of collection. After 3 days, I could find at least 3, maybe 4, new fry (they simultaneously sit really still and move really fast, so counting them was a challenge), in addition to the two older fry.

Fast forward to yesterday. I could find only 3 live babies in the breeder box, and I definitely found 1 dead one yesterday. Confusingly, there was only 1 mm SL difference between the smallest and largest fry. I don't know if the largest fry died and the three alive were all young (1 week old), or if the growth is so slow that the largest fry gained only 1 mm SL over the last week. Time will tell.

I bought another breeder box, so the next time the parents spawn, I won't need to combine the eggs with the existing fry.

Cheers, Eric

[bekateen]

Fry growth update. Largest fish is 24 days old and 8mm SL. Still have two fish. They continue to grow at only 1mm per week! Dang that's slow.

Cheers, Eric

[bekateen]

Direct YouTube link: Amblydoras nauticus 25 days old

[CoryWally]

Hi Eric,
Its been great following your progress with the Amblydoras . I'm sure you've got aquatic publications queuing for the print exclusive, but the CSG Journal would love to feature your experiences!

Cheers,
Mark

[bekateen]

Thanks Mark! I have to confess I haven't figured out where to send any paper I write. Haven't given it too much thought, but I do intend to write it up.

In the meantime, this morning I arrived at work to discover SPAWN #3. Happened overnight after a big water change yesterday afternoon.

I lost count of the eggs, but it's at least 147. Some are definitely bad already. After taking this photo, I picked out the worst eggs and moved them to one end of the box (in case the eggs were still viable) and moved the good eggs to the opposite end of the breeder box. I then treated the breeder box with a few drops of methylene blue to inhibit fungus. The box is a slow flow through box, so the meth blue won't stay concentrated very long. I think I'll treat the whole box with Pimafix, which is an antifungal that is well-handled by all the fish I've ever used it on.

Also this time, I started again to collect the eggs using the turkey baster, but after 7 rows of doing that (133 individual cells in the egg crate), I had a "V-8" moment and switched to a narrow tube aspiration method. I don't know if I got as many eggs this way, but this was much faster. Also, as I experienced with the last big spawn, 80% or more of the eggs this time were located in the 5 rows of egg crate under the spawning mop. Very few eggs were collected from the rows away from the mop. Obviously this could have been affected by me switching methods of egg collection, but I had already started to notice egg numbers dropping in the last rows I was searching with the turkey baster method; I think the parents spawn under or in the mop.

Also this time, I was lucky to find more eggs attached in the mop, about 10 eggs instead of the 3 or so I found the last two times.

Cheers, Eric

[bekateen]

I lost count of the eggs, but it's at least 147. Some are definitely bad already. After taking this photo, I picked out the worst eggs and treated the breeder box with a few drops of methylene blue to inhibit fungus. The box is a slow flow through box, so the meth blue won't stay concentrated very long. I think I'll treat the whole box with Pimafix, which is an antifungal that is well-handled by all the fish I've ever used it on.

After sorting the eggs, it looks like about 1/3 of them are bad. But when I initially collected them about an hour ago, I saw very few that looked bad. This makes me wonder if it's my handling that is damaging them. I know that some eggs go through developmental stages where they are more or less sensitive to being disturbed. I wonder if the Amblydoras eggs would be better off if I left them for one day in the parents' tank (they would still be protected from being eaten by the egg crate). I will try that! When I find the next spawn, I will leave the eggs in the parent tank for one day and then collect them on the second day to see if this improves the percent of eggs developing.

Cheers,
Eric

[bekateen]

Next morning - I removed all the bad eggs (inflated opaque white jelly coats, no obvious yellow yolks). Counting only the remaining good eggs, I still have around 92 eggs (+/- 5). I think that's pretty good!

Cheers,
Eric

[bekateen]

Amblydoras nauticus egg/embryo, 33-47 hours post-fertilization (pics taken at 7pm today, thus the time frame). Should hatch by tomorrow.

[bekateen]

Based on the first spawn (new eggs Tuesday morning, eggs hatched Thursday morning), the eggs from this most recent spawn should have hatched today. But this morning, which would be the second day, so far no eggs have hatched. Thankfully, only one egg went bad overnight. I still have about 90 eggs.

Maybe they'll hatch later today... Maybe they won't have hatched until tomorrow morning. On the second spawn, I didn't check for hatchlings until the third day, so maybe a 2.5 to 3-day incubation is a more accurate estimate of incubation time than my original 2 day incubation inference.

I'll be checking all day today!

Cheers, Eric

[bekateen]

They still haven't hatched yet! Dang. But at least they look like they'll go at any moment.

(Pic taken at 10AM on 4/28)
Cheers, Eric

[bekateen]

I'm trying to back calculate the age of these most recent eggs:

• No eggs at 7PM Monday (4/24)
• New eggs at 9AM Tuesday (4/25) (egg pics taken)... Eggs must be between 0-14 hours old at this point, since they were laid between the time I left school on Monday and arrived on Tuesday.
• Next pic at 6PM Wednesday (4/26)
• Most recent pic at 10AM Friday (4/28)

9AM Tuesday to 10AM Friday = 73 hours (minimum age of egg at time of most recent photo)
7PM Monday to 10AM Friday = 87 hours (maximum age of egg at time of most recent photo)

Wow, they sure have changed a lot in 40 hours. So how did they hatch in just two days after the first spawn? Were the eggs already laid the previous weekend and I just didn't see them the day before? The world may never know.

[bekateen]

Finally hatching now, 80-94 hours post-spawning. Incubation time, 3-4 days.

[bekateen]

Spawn #3 almost entirely hatched by 4pm today. Surprisingly a few fry have not yet escaped their jelly coats.

Cheers, Eric

Amblydoras nauticus fry on day of hatching

[bekateen]

The oldest

Amblydoras nauticus

baby is now 42 days (6 weeks) old. Here it is today. Believe it or not, this "big" baby is still only 10mm SL! The other old fry is smaller. And I still have an uncountable number of tiny fry from the most recent spawn.

[bekateen]

UPDATE: Here's the oldest fry and a younger one. The oldest is turning two months old this week.

Cheers, Eric

[bekateen]

Another spawn (SPAWN #4) found today. I didn't inspect closely for eggs yesterday, so I can't say with certainty the age of these eggs, but they do look fresh.

My guess is about 50-60 eggs, and I removed 16 bad eggs about 5 hours after collecting the eggs. As before, these eggs didn't look bad when I collected them, but after only a half day these 16 had turned white.

[bekateen]

Another

Amblydoras nauticus

spawn (SPAWN #5) overnight. This one was pretty big. I collected 111 eggs, five on the spawning mop and the rest trapped in the egg crate false floor. Only two of the eggs I collected looked bad at the time I collected them. I will be curious to see how many spoil in the next 24 hours.

I'm really pleased with how easy it is to protect and collect the eggs using this egg crate. It took me about 10 minutes to gather all these eggs.

Cheers, Eric

[Shane]

I may have missed it but how are you collecting them?
-Shane

[stuby]

Awesome! Congratulations Eric, keep up the good work and thank you for all the pictures and info! Would love to try some myself someday.

Take care,
Chuck

[bekateen]

Awesome! Congratulations Eric, keep up the good work and thank you for all the pictures and info! Would love to try some myself someday.

Take care,
Chuck

Thanks Chuck. I'm sure you would succeed. You're a terrific breeder!

I may have missed it but how are you collecting them?
-Shane

Hi Shane,

It's a simple siphon, but the hose is chosen for its diameter - the hose is sufficiently narrow that I can insert it into individual square openings of the egg crate; the narrow tube has a low flow rate so it's relatively gentle and it doesn't suck much water out of the tank. The outlow end of the hose rests under water in a 5-gallon collection bucket, again to make the outflow as gentle as possible.

• I dip the hose in each hole of the egg crate and suck out eggs with a little sand; this removes about 3 gallons of water from the tank.
• After getting the eggs, I pour off most of the removed water until there's only about 200-300 ml water volume with the eggs and sand remaining in the bucket.
• I then decant the water with eggs using gentle swirling (to separate the eggs from any sand) and pour the water with eggs in a 500 ml plastic bowl.
• I then separate the eggs (about 10 eggs at a time) from residual debris using a pipet and transfer the eggs to the incubation box.

It sounds laborious but really it is so much better than my previous method where I inserted the turkey baster in each square of the egg crate and blasted water to force eggs up into the tank water, then I'd try to catch the eggs while floating (which I believe I did make a video of previously).

I'll make a video of the siphoning next time I collect eggs.

Cheers, Eric

[Shane]

Please do. I have been working with some tetra spp (rummynose and wild Bleeding Hearts) to build up some nice schools for Chewy's tank. Your method would seem to work for them as well.
-Shane

[characinkid]

HI Eric, Thank you for the continued information, but more importantly for me, the inspiration to try breeding fish that others have not done so before. There are lots of fish that I would like to try and you show that it is possible with the right care, perseverance and ingenuity.
Thanks

[sturiosoma]

Another

Amblydoras nauticus

spawn (SPAWN #5) overnight. This one was pretty big. I collected 111 eggs, five on the spawning mop and the rest trapped in the egg crate false floor. Only two of the eggs I collected looked bad at the time I collected them. I will be curious to see how many spoil in the next 24 hours.

I'm really pleased with how easy it is to protect and collect the eggs using this egg crate. It took me about 10 minutes to gather all these eggs.

Cheers, Eric

Eric do you have an air stone in your breeder box.

Jeanne

[bekateen]

HI Eric, Thank you for the continued information, but more importantly for me, the inspiration to try breeding fish that others have not done so before. There are lots of fish that I would like to try and you show that it is possible with the right care, perseverance and ingenuity.
Thanks

You're welcome. Please yes, keep trying to breed new stuff! And don't give up after failing multiple times. Case in point, my Microglanis aff. poecilus - I've had several spawns out of them since they started breeding, but not one egg has hatched so far. I know it's possible. I just need to figure out the "magic recipe!"

Eric do you have an air stone in your breeder box.

Jeanne

Hi Jeanne. No, I do not have an airstone in my Amblydoras box; aeration is by the bubbler pumping water into the box. (I did add an airstone to my Microglanis aff. poecilus egg box, but those eggs didn't hatch). The Amblydoras eggs hatch well. I had about 30% of the eggs turn cloudy (importantly, not fuzzy) in the previous spawns, but in the eggs from yesterday, I've had less than 10% turn cloudy. I think the eggs die if handled roughly, so yesterday when I harvested the eggs, I tried to be very gentle.

Actually, my past spawns of Amblydoras have suffered more mortality by the babies swimming into the foam and getting stuck than by other factors, as far as I can tell. So today I moved all the eggs from the last two spawns into one of the German Breeder Rings sold by Swiss Tropicals (https://www.planetcatfish.com/common/ad ... ?ad=swiss7). This should drastically improve hatching survival, but it will make feeding more difficult, because microworms (my first foods) can escape through the bottom of the ring.

[bekateen]

The eggs from the May 28 spawn have started hatching in the German Breeder Ring. Fingers crossed!

[bekateen]

Very nice hatch of last two spawns (28 May and 30 May). At least 125 fry, maybe 135, swimming here.

Video soon.

Cheers, Eric

[bekateen]

Here's a video of all the fry from the last two spawns. Enjoy.

Cheers, Eric

Direct link: Lots of baby Amblydoras nauticus!

[sturiosoma]

Very nice hatch of last two spawns (28 May and 30 May). At least 125 fry, maybe 135, swimming here.

Video soon.

Cheers, Eric

Eric are you having trouble feeding I think you said you were concerned about the microworms going thru the mesh bottom.

Jeanne

[bekateen]

Eric are you having trouble feeding I think you said you were concerned about the microworms going thru the mesh bottom.

Jeanne

Hi Jeanne,

Yes they do slip through the screen. I still feed live microworms but I drop them on top of the leaves in the ring, hoping to delay the loss of worms, and I also feed a soaked slurry of water with Repashy powder.


Cheers, Eric