Egg hatching problems

[Anthony1976]

Hi guys I hope someone can help me out with hatching Cory eggs. Been trying a few times without success to hatch out albino Cory eggs. Been using a tub with tank water floating in the main tank with a few drops of meth blue from the start then clearing the blue out at the end of day two before they hatch . I have also tried leaving them in the meth blue for the full time but with the same result and I’m really confused . On day three I start to see a white bump which sticks out from each egg it looks kind of like the fry has tried to burst out but has died I leave them a couple of days more with no success and I’m really stumped as to why this keeps happening . Any ideas as to what I can try next? Thanks

 

[CassCats]

what is your pH?
If it is too alkaline, add aldercones. Sometimes high alkaline ph can make the egg too hard to hatch out of.

 

[ghyti]

Could also try using rain water in the hatching bowl. Jungle Fungus Cure tabs work just as good as Meth blue and don't have to be removed right away. 1/2 tab per gallon.

 

[Anthony1976]

Thanks for the help, my tapwater is very hard where I live so I mix it with rainwater 50/50 and add equilibrium to replace the minerals and it is still around 7.4

 

[ghyti]

I have pH of 8.3 and gH of over 300 ppm and hatch cory eggs all the time so it probably isn't your water hardness. How many cories in the group? Could be your breeders are weak for some reason. Maybe try a different diet. I would try 100% rainwater or RO water (fresh water, not tank water) without the equilibrium in the hatching container for one batch of eggs to see if that helps. Also I would try alder cones instead of meth blue for one batch, or maybe some other fungicide like Hydrogen Peroxide. Also make sure there is an air stone or other air source in the hatching container so the water circulates some.

 

[Anthony1976]

I have pH of 8.3 and gH of over 300 ppm and hatch cory eggs all the time so it probably isn't your water hardness. How many cories in the group? Could be your breeders are weak for some reason. Maybe try a different diet. I would try 100% rainwater or RO water (fresh water, not tank water) without the equilibrium in the hatching container for one batch of eggs to see if that helps. Also I would try alder cones instead of meth blue for one batch, or maybe some other fungicide like Hydrogen Peroxide. Also make sure there is an air stone or other air source in the hatching container so the water circulates some.

Thanks for the help, I have seven Cory’s I bought at the same time. I was successful in hatching around fifty eggs around six months ago and if I remember rightly it was a bigger male that was going around with the female. This past few months it has always seemed to be one very small male that does all the chasing and t positions. Could it be that this male is no good?? To condition them I feed frozen brineshrimp, bloodworms, and api bottom feeder pellets. The Cory’s are around 15 months old I believe. I always use an air stone in the hatching container

 

[CassCats]

I have pH of 8.3 and gH of over 300 ppm and hatch cory eggs all the time so it probably isn't your water hardness. How many cories in the group? Could be your breeders are weak for some reason. Maybe try a different diet. I would try 100% rainwater or RO water (fresh water, not tank water) without the equilibrium in the hatching container for one batch of eggs to see if that helps. Also I would try alder cones instead of meth blue for one batch, or maybe some other fungicide like Hydrogen Peroxide. Also make sure there is an air stone or other air source in the hatching container so the water circulates some.

Your water is far too hard for corydoras longterm.

 

[Derekshatch]

i have a small male and have no problem hatching the eggs out. It could be because either you are not getting rid of all of the fungus eggs, you are not doing water changes 3 times a day on container or the temp change during the water changes is too drastic.

 

[CassCats]

i have a small male and have no problem hatching the eggs out. It could be because either you are not getting rid of all of the fungus eggs, you are not doing water changes 3 times a day on container or the temp change during the water changes is too drastic.

3 times daily is overkill, they should only need 1 time a day change

 

[Derekshatch]

Well I do my hatching in like a 1/2 gallon or 1 gallon tub so it needs to be changed often but it just depends on how big your hatching container is.

 

[CassCats]

Well I do my hatching in like a 1/2 gallon or 1 gallon tub so it needs to be changed often but it just depends on how big your hatching container is.

Even on that is overkill, I use 1/4 totes for eggs and wrigglers and move them to a 2.5g once they free swim.

And 1x daily is fine

 

[ghyti]

Your water is far too hard for corydoras longterm.

That is what I keep telling my well but nothing changes. WHat do you mean by 'long term'? I got my Aeneus breeders in 2011, my Ehrhardti breeders in Oct. 2012, my CW021 breeders in 2013, my Metae and Panda breeders in 2015. Only ever had problems with the CW021. I had to put them in half rain water for the eggs to hatch.

 

[CassCats]

That is what I keep telling my well but nothing changes. WHat do you mean by 'long term'? I got my Aeneus breeders in 2011, my Ehrhardti breeders in Oct. 2012, my CW021 breeders in 2013, my Metae and Panda breeders in 2015. Only ever had problems with the CW021. I had to put them in half rain water for the eggs to hatch.

@Byron Is the best to explain this.

But it causes build up of minerals in their kidneys that they aren't evolved to handle, causing them to die earlier than their normal healthy lifespans.

While there are a few hard water corydoras species, the maximum range is 268ppm for even the hardest water ones.

 

[ghyti]

@Byron Is the best to explain this.

But it causes build up of minerals in their kidneys that they aren't evolved to handle, causing them to die earlier than their normal healthy lifespans.

While there are a few hard water corydoras species, the maximum range is 268ppm for even the hardest water ones.

None of these have died and they all are still spawning regularly. What is the 'normal' lifespan of a corydoras ?
"maximum range is 268ppm" maximum for what.? Do they all die off at 269? Aquarium cories are so far removed from wild that the wild parameters are all but meaningless.

 

[CassCats]

None of these have died and they all are still spawning regularly. What is the 'normal' lifespan of a corydoras ?
"maximum range is 268ppm" maximum for what.? Do they all die off at 269? Aquarium cories are so far removed from wild that the wild parameters are all but meaningless.

268ppm GH, the water hardness.

A few decades of captivity does not change millions of years of evolutionary needs.

Cories can live 7-10 years or more average, some records into their 40s.

Place this in perspective.

Being kept outside of parameters they expect from their evolution, their biology isn't adapted for that. This makes their bodies work harder just to live. In turn, this stresses their immune system. This makes them more prone to illnesses and bacteria should anything take over a tank. Fish kept in the wrong environments are often the first to be stricken with disease outbreaks, even trivial.

Sure, theyre eating and swimming, because theyre surviving, but the internal stresses we don't see may very well shorten their lifespan.

@Byron there are studies on this, necrosis on fish who have died from this.