My Cory Catfish Fry died only a day after they're born :(

[gabrielgalhano]

Hello!

About a week ago my corydoras aeneus decided that they wanted to increase their family. I collected about 200 eggs and 3 days after the fry started to hatch. However, one day later they all started to die, one after another.

Does anyone know anything that could justify this happening?

Thank you in advance

 

[Byron]

Members will need to know the data on this tank/water. Can you provide the parameters (GH, KH, pH and temperature are the parameters)? And have you tested for ammonia, nitrite and nitrate, and if yes, what are the numbers? What sort of tank were the fry put in? Did you feed them anything; they would not be feeding that soon after hatching, but "food" might have polluted the tank/water, and all possibles need to be covered.

I just posted in your other thread on high nitrates...knowing the number is important here.

 

[Colin_T]

If they die within a day of hatching it is usually caused by poor water quality, low temperature, or physical damage when people try to remove the eggs from the tank.

If they die a few days after hatching, it can be poor water quality or starvation.

 

[gabrielgalhano]

Members will need to know the data on this tank/water. Can you provide the parameters (GH, KH, pH and temperature are the parameters)? And have you tested for ammonia, nitrite and nitrate, and if yes, what are the numbers? What sort of tank were the fry put in? Did you feed them anything; they would not be feeding that soon after hatching, but "food" might have polluted the tank/water, and all possibles need to be covered.

I just posted in your other thread on high nitrates...knowing the number is important here.

The water parameters were all within the normal (I follow the sera quick tests reference values), or at least I think they were. Even though because I had some guppy fry the day earlier and they all did good! That's why I was so confused about why the cory fry just died. It occured to me that maybe the water parameters were already not ideal and the cory fry are more sensitive to water parameters changing?
The cory fry were in a plastic container, I removed the eggs from the glass of the tank into this plastic container that was with the same water of the tank and floating in the tank.
I didn't feed them, since I read that they don't need to be fed in the first days after hatching due to the yolk sack.

If they die within a day of hatching it is usually caused by poor water quality, low temperature, or physical damage when people try to remove the eggs from the tank.

If they die a few days after hatching, it can be poor water quality or starvation.

As I said before, I think the water parameters were good due to the guppy fry that were born one day earlier, but I can't be certain
The temperature of the tank is 26ºC (78F).
I was very careful when removing them from the tank, also because it was my first time. But that could indeed have happened

 

[Sgooosh]

If they die within a day of hatching it is usually caused by poor water quality, low temperature, or physical damage when people try to remove the eggs from the tank.

If they die a few days after hatching, it can be poor water quality or starvation.

i think it is starvation by how they described it...
were there almond leaves and stuff?
did you feed them
and what did youfedd them(if you did)

 

[gabrielgalhano]

i think it is starvation by how they described it...
were there almond leaves and stuff?
did you feed them
and what did youfedd them(if you did)

No, I only found out about the almond leaves a couple days ago on my researches...
I didn't feed them because I read that due to the yolk sack they dont need to be feed in the first day after hatching...

 

[Sgooosh]

No, I only found out about the almond leaves a couple days ago on my researches...
I didn't feed them because I read that due to the yolk sack they dont need to be feed in the first day after hatching...

yep!
the infusoria on leaves and whatnot are a secondary food source

 

[gabrielgalhano]

yep!
the infusoria on leaves and whatnot are a secondary food source

but could be the lack of the almond leaves the reason why they all died?

 

[Sgooosh]

but could be the lack of the almond leaves the reason why they all died?

hm i dont think thats the problem
did they have the yolk when they died

 

[gabrielgalhano]

hm i dont think thats the problem
did they have the yolk when they died

some of them still had a big yolk, some didn't

 

[Sgooosh]

hm i dont think thats the problem
did they have the yolk when they died

Yeah...
parameter problem...

 

[gabrielgalhano]

Yeah...
parameter problem...

maybe the parameters were already not that good and i just didnt noticed in time
I guess the guppy fry are more resistant to those changes...
thanks for your help!

 

[Sgooosh]

maybe the parameters were already not that good and i just didnt noticed in time
I guess the guppy fry are more resistant to those changes...
thanks for your help!

what are the exact parameters?

 

[gabrielgalhano]

what are the exact parameters?

I only tested the water almost a week after they died, not only because it was about time but also because i started to notice some changes in the other fish behaviour. At the time they died, i thought the parameters were all within the reference values, but when I tested the water a week later (the strps I use test for nitrate, NO2, GH, KH, pH and Cl), all the values were good except the nitrate that was about 100 mg/L, and the NO2 that was around 5 mg/L

 

[Sgooosh]

I only tested the water almost a week after they died, not only because it was about time but also because i started to notice some changes in the other fish behaviour. At the time they died, i thought the parameters were all within the reference values, but when I tested the water a week later (the strps I use test for nitrate, NO2, GH, KH, pH and Cl), all the values were good except the nitrate that was about 100 mg/L, and the NO2 that was around 5 mg/L

alright...
meet you on the other tnread then.