Corydoras Sterbai eggs not hatching because of hard water?

[Guppysnail]

On 5/30/2024 at 6:48 AM, Flavoi1 said:

I never found empty eggshells

I never find shells either. I can’t speak scientifically on this but the tail moves towards the outside and pops out and the entire egg becomes the fish. Here is one of my Pygmy a bit farther along.  You can see the body appears as if it wrapping around the egg  

Once they hatch and start moving roughly 2 days I add a very very tiny amount of sera micron or golden pearls 5-50 for the smallest 3x a day. Then as they grow I size up to hikari first bites then northfin fry. 
I do keep the bottom of the box very clean since they lay in the fluff on the floor.  I had a batch i shattered my wrist during that I did not keep the floor clean each night. They had tail and barbel issues. 
Corydora are liw stress/ low maintenance fry. They are very sturdy and require nothing more than food and clean water.  
 

To clarify the egg on the left is Pygmy unhatched the big egg is melini 

[Flavoi1]

@Guppysnail

 Sooo... just a few hours ago I told you that I would look into your suggestion as soon as I had a new batch of eggs. 

Here are 25 of them 🙃

        

 

I have diluted my tap water with RO water to a GH of about 200 ppm (11.2ish dGH) and the PH is about 7.3 (all after adding the appropriate amount of dechlorinator).
The box is placed inside the tank to keep the temperature at a constant 24°C (75ish °F) and I have added some light aeration.

I'm going to start a new batch of BBS in my Hobby BS hatchery dish,
If you only need a few BBS a few times a day for a few days, I like the hatchery dish the most.

Wish me luck, y'all 🙂 I'll let you know how it goes once I see some notable progress

[Guppysnail]

On 5/30/2024 at 1:03 PM, Flavoi1 said:

added some light aeration.

Turn it up. I have used a tumbler before. The circulation keeps fungus from taking hold. Flow is good. 
 

YOU GOT THIS 🎉

Looking forward to baby photos in a few day. 

[Flavoi1]

On 5/30/2024 at 7:07 PM, Guppysnail said:

Turn it up.

Done 🙂 and thanks alot for your help.

[Flavoi1]

@Guppysnail I don't have access to methylene blue, but I do have catappa leaves. Do you think it would help if I added some?

[Guppysnail]

On 5/30/2024 at 1:21 PM, Flavoi1 said:

@Guppysnail I don't have access to methylene blue, but I do have catappa leaves. Do you think it would help if I added some?

I add nothing but lots of water movement. Using tap and ro I only have infertile (solid white) eggs fungus. I do not use meth blue on any eggs. 
 

 

I do not use cattappas either. I find more fungus grows using botanicals than without 

[Flavoi1]

It's been 3 days since I put the eggs in the breeding box. Today I noticed 2 eggs that had turned white and discarded them.

Here are some shaky videos I took with my phone and a microscope (posted to imgur cause way to big of a file):
Corydoray Sterbai - 3ish days old egg- heartbeat bottom right
Corydoray Sterbai - 3ish days old egg- moving at the end of the video

Here you can see 2 eggs stuck together. The egg on top has a healthy fry in it and the bottom one is unfertilised and has started to go bad. I noticed that the unfertilised egg is completely opaque under the microscope, but with the naked eye you can only see a small white spot in the middle of the egg.

Edited June 2 by Flavoi1

[Rube_Goldfish]

On 5/30/2024 at 7:04 AM, Guppysnail said:

I do keep the bottom of the box very clean since they lay in the fluff on the floor.  I had a batch i shattered my wrist during that I did not keep the floor clean each night. They had tail and barbel issues. 

Not to hijack this thread*, but can you elaborate a little on your procedure for keeping the bottom of your breeder box clean? I'm using the Ziss Premium Breeder Box for the first time, and the airline seems to be pulling in mulm (or it's naturally occurring) that's now making a small layer on the floor:

I know I can siphon with an airline or use a turkey baster, but I don't know how to do that without sucking up eggs and fry I can barely see. Any suggestions?

* I can repost this as a separate question if you'd prefer, @Flavoi1

[Flavoi1]

On 6/4/2024 at 7:35 PM, Rube_Goldfish said:

I can repost this as a separate question if you'd prefer

Feel free to ask for advice, you can do so here in this thread.

 

On 6/4/2024 at 7:35 PM, Rube_Goldfish said:

I know I can siphon with an airline or use a turkey baster, but I don't know how to do that without sucking up eggs and fry I can barely see. Any suggestions?

As far as I'm concerned, I use an airline with my finger on the end to stop immediately if I notice an egg/fry being sucked up. If you don't have a big difference in elevation, the siphon will also be slower.
Once the fry have hatched you can add some snails to help clean up the muck, but before then they may eat the eggs.

 

If you're still on in a couple of hours I'll post an interesting update with some great video content concerning my corry eggs.

[Guppysnail]

On 6/4/2024 at 1:35 PM, Rube_Goldfish said:

Not to hijack this thread*, but can you elaborate a little on your procedure for keeping the bottom of your breeder box clean? I'm using the Ziss Premium Breeder Box for the first time, and the airline seems to be pulling in mulm (or it's naturally occurring) that's now making a small layer on the floor:

I know I can siphon with an airline or use a turkey baster, but I don't know how to do that without sucking up eggs and fry I can barely see. Any suggestions?

* I can repost this as a separate question if you'd prefer, @Flavoi1

I cut an airline at an angle. You can zip tie to a chopstick. I use a magnifying glass. I do not worry about it until I can see them clearly.  
When I say clean I mean not a half inch deep with mulm. 
This has Pygmy Cory babies and CPD that are still tiny enough to get sucked up so I leave it. 

This is melini and Pygmy large enough I can clean up around them they are days from release to a grow out  

 

Hastatus with Daisy rice fisH.  It will be easily 2-3 weeks before I touch this one 

Also I siphon to a white or clear small dish then double check with a magnifying glass. To rescue water ride contestants. 

[Guppysnail]

@Flavoi1 did your eggs hatch?

[Flavoi1]

@Guppysnail yes 🙂

I'm cooking dinnet atm but here's a sneak peek: Corydoras Sterbay fry - a few seconds old - pulsating heart and visible blood flow.
Will poste some pics and questions later, I hope You'll be on once I get to it.
 

[Flavoi1]

As mentioned above, the eggy hatched a few hours ago.

Here are some pictures of em:

 

And here is the setup of the hang on box. I kept the air stone in and added some moss for cover and small critters. I also added some snails and cherry shrimp as cleaners.

Here you can see the flow rate of the water.

@Guppysnail The fry hatched sometime in the last 12 hours or so.  I'll be getting up to go to work in about 7 hours. Should I add some sera micron to the bottom of the tank before I go to work or do you think I should wait until I'm home in about 19 hours?
Do you have any other tips or things to consider?

[Guppysnail]

On 6/4/2024 at 3:46 PM, Flavoi1 said:

As mentioned above, the eggy hatched a few hours ago.

Here are some pictures of em:

 

And here is the setup of the hang on box. I kept the air stone in and added some moss for cover and small critters. I also added some snails and cherry shrimp as cleaners.

Here you can see the flow rate of the water.

@Guppysnail The fry hatched sometime in the last 12 hours or so.  I'll be getting up to go to work in about 7 hours. Should I add some sera micron to the bottom of the tank before I go to work or do you think I should wait until I'm home in about 19 hours?
Do you have any other tips or things to consider?

Wait. They are still absorbing the yolk. The last thing you want is a big ammonia spike while you are not there to monitor.