Help with eggs

[J355ie]

I have Chinese fire belly newts this is my third year of them breeding
But I’m struggling to keep the eggs healthy
After about a week-10 days the egg sacks start breaking down and become so thin the developing lave just pop out with them being so premature they never survive more than 3 days

Any ideas why my egg sacks keep breaking down

Sorry the photos are not very good

One is of the lava
The other of the egg sacks
The dark area is the clear bit that just seems to be dissolving

 

[minorhero]

I can't make anything out with your photos.

Are you putting the eggs into a cycled aquarium using tap water?

 

[J355ie]

I can't make anything out with your photos.

Are you putting the eggs into a cycled aquarium using tap water?

I’m using the water from the main adult tank

 

[minorhero]

Is it a cycled tank or just a jar filled with old water

 

[J355ie]

Is it a cycled tank or just a jar filled with old water

When they start laying I put the eggs in a 10litre tank using water from the main adult tank
I also have a sponge air filter to stop the water stagnating

 

[NKmememachine]

I've had a couple of similar cases with alpine newt eggs although they tend to hatch in about 10 days normally. If I remember correctly, the membrane that protects the embryo gets stretched thinner as the egg progresses naturally but they shouldn't be hatching that early as you've stated.
PH levels being too high or too low would be my mostly uneducated guess, so perhaps checking the water levels may give you an answer as to why that's happening. Some newt species are more resilient to PH fluctuations as adults but their eggs and larva are less so. If that's not the case, then there might be something going on with the female producing the eggs or perhaps a genetic issue.
One anecdotal note to keep in mind. I had a couple of early hatchlings that survived development outside of their membranes. It's far from ideal for them, but the membrane seems to mainly be there to protect them from diseases and dirty water while their immune system is developing. If you transfer these faulty eggs to some "Holtfreter's solution" if you are able to get or prepare some, or perhaps just some distilled water, you may end up with some survivors of this early "de-shelling" problem.
Good luck!