Hatching and raising corydoras fry

[Karen B.]

Greetings!

Apparently my false julii corydoras have been having a lot of fun. Each morning I wake up to 5-15 eggs.

I am however having trouble hatching them. I watched a lot of video, especially @Irene - I put my eggs in a small container with a few drop of mythilene blue and an air stone. I let it float in the main tank, I remove the bad eggs, I do WC but only 1 hatched so far. A lot of them are actually turning darker...

I had the idea to transfer them in my 10 gallons where I raise clown killifish fry but the substrate is gravel, not sand.

Any advice on what I should do differently?

Thank you!

[KBOzzie59]

I hatch mine in a Fluval outside the tank breeder box.  It pulls in water via a lift tube and drains back into the tank.  I also run a very small (80 GPH) power head on minimum flow until they hatch (keeps the fungus off), attach a piece of sponge medium/coarse over the intake.  I never use any chems.   I was unable/unwilling to pull all the eggs from this brood because she laid 99% of them in that big mess of moss in the background.

 

Breeder Box

Power Head

 

 

Here is one setup waiting on my Albino Corries to spawn.

Edited July 2, 2021 by KBOzzie59

[Karen B.]

On 7/2/2021 at 1:09 PM, KBOzzie59 said:

I hatch mine in a Fluval outside the tank breeder box.  It pulls in water via a lift tube and drains back into the tank.  I also run a very small (80 GPH) power head on minimum flow until they hatch (keeps the fungus off), attach a piece of sponge medium/coarse over the intake.  I never use any chems.   I was unable/unwilling to pull all the eggs from this brood because she laid 99% of them in that big mess of moss in the background.

 

Breeder Box

Power Head

 

 

Here is one setup waiting on my Albino Corries to spawn.

That’s so cool, I already own that breeder box. I would just need the power head. How long do you keep them in there? How often do you clean the bottom?

[KBOzzie59]

I'll probably keep them in there 30'ish days.  No I do not clean the bottom, they are catfish, they like the mulm.

And as I finished that last post the Albinos started spawning.  I have to be on my game with them, they like to eat their eggs.

[mountaintoppufferkeeper]

On 7/2/2021 at 10:51 AM, Karen B. said:

Greetings!

Apparently my false julii corydoras have been having a lot of fun. Each morning I wake up to 5-15 eggs.

I am however having trouble hatching them. I watched a lot of video, especially @Irene - I put my eggs in a small container with a few drop of mythilene blue and an air stone. I let it float in the main tank, I remove the bad eggs, I do WC but only 1 hatched so far. A lot of them are actually turning darker...

I had the idea to transfer them in my 10 gallons where I raise clown killifish fry but the substrate is gravel, not sand.

Any advice on what I should do differently?

Thank you!

Congrats on the eggs and 1 hatched fry. The good news is once they start laying they are unlikely to ever stop and you have plenty of trial and error on how to best hatch and raise fry in your set ups.

I've done panda cory in a heavily planted tank with plecos loaches and tetras. Plants were heavy enough that my 6 cory group blew up to 300 ish of all sizes when I broke down the 55 a year later. it was excessive. I would probably try the 10 gallon with the killies if that was what I had available; my clown killies never leave the top and I would say are somewhat safe to try with the cory eggs and gravel. I haven't yet tried the methylene blue with anything but did just purchase the powder form and mixed my own up to have handy should I need it. 

I have had good success with that outside fry box set up, I use that 80 gph pump as well but use it in the main tank on the end of the uplift tube and in place of the airline connector piece. I have also done an egg tumbler when hatching separately within the main tank and then just removed the fry to another tank when ready. 

[Georgiapeach88]

I think my albino corys had some fun after I went to work ?

[Karen B.]

On 7/2/2021 at 6:42 PM, Georgiapeach88 said:

I think my albino corys had some fun after I went to work ?

They don’t miss us when we are not there! 😅😅😅

[Georgiapeach88]

Should I move them or leave there? It’s only them and nerites In tank so far 36 gal 

[Karen B.]

On 7/2/2021 at 6:56 PM, Georgiapeach88 said:

Should I move them or leave there? It’s only them and nerites In tank so far 36 gal 

Sorry for the late reply!

it depends of your settings. Is it densily planted? I heard parents can eat their eggs and fry. 

[Georgiapeach88]

On 7/5/2021 at 1:44 PM, Karen B. said:

Sorry for the late reply!

it depends of your settings. Is it densily planted? I heard parents can eat their eggs and fry. 

Yeah it’s decently planted. I’m still not 100%if these are corydora eggs or my nerites. I know they say sesame seed looking eggs are narite snail eggs. But I honestly can’t tell 

[Georgiapeach88]

[Karen B.]

On 7/5/2021 at 1:50 PM, Georgiapeach88 said:

Yeah it’s decently planted. I’m still not 100%if these are corydora eggs or my nerites. I know they say sesame seed looking eggs are narite snail eggs. But I honestly can’t tell 

Pretty sure they are cory eggs. Nerita’s are smaller

[Odd Duck]

Looks like cory eggs.  Nerite eggs are opaque, cory eggs are translucent.  These are bronze cory eggs.

 

 

[Karen B.]

On 7/5/2021 at 2:01 PM, Odd Duck said:

Looks like cory eggs.  Nerite eggs are opaque, cory eggs are translucent.  These are bronze cory eggs.

 

 

Oooh! You have so many!

I got mine to spawn. Sadly the fry only live one day. I wonder if it’s because I retrieve them with a pipette… maybe it damages the yolk sac or something? I will try to find another way.

[Georgiapeach88]

Thanks @Odd Duck these eggs seem a bit opaque. But my corys are young. So maybe infertile eggs. Will leave them be and keep an eye on them to see if they change color. Would love to get little Cory fry 😁

[Odd Duck]

@Karen B. It’s probably safer to move eggs than fresh hatched fry.  I’ve seen videos of people using old gift/credit cards to gently scrape the eggs off the glass.  You’ll miss some if they’ve laid some on the plants, but if you have enough plants, you may still get babies growing up in the tank.  I’ve had enough plants in my tanks with cories that the population has only very slowly increased and I haven’t made any effort to move eggs away from the adults.