Infertile Eggs and Twins

[ian]

My favourite snail laid eggs then died a few days later so i thought it was important to keep a few from the batch to continue her bloodline. I kept 15 and have been getting impatient and cracking them open ive opened 6 so far. I have found that 3 of the 6 were infertile, which is alot for fulica assuming its representative of the whole batch! Another one had a snail of 2 mm in which was alive but then died after just a day. The next one had a tiny snail in, which i was confused about because they were laid 2 weeks ago and are kept on my radiator which is really hot! Anyway the next one i opened had two tiny little twin snails in both about 1mm!
I have 2 questions;
Why are the eggs not hatching and why are the snails so tiny ive had them for 2 weeks in a very warm position and usually my fulicas only a few days to hatch?
Secondly how often do twins actually occur, i was very surprised to see them both in the egg!

[Paul]

If they are on the radiator perhaps it was too hot at some point? Radiators fluctuate, you'd need a max/min thermometer to know for sure.

[sezzy5889]

maybe you didn't leave them long enough, you shouldn't crack them open, premature snails are unlikely to live

[ian]

I only cracked a few, im inpatient and wanted to check what they were up to in there. I dont have any thermometers but im going to get one i think im actually keeping them too hot, they are up next to the radiator which is very hot, they have their own room which is like a sauna! What temp should i have for the snails (i have fulica, dimidiata, iredalei and marginata) and what temp do the eggs need?
This is the first batch i have ever removed from the tank, does moving them make it less likely for them to hatch? If i keep the eggs a bit cooler now do you think they might start develope again and one day hatch or are they dead???

[Deleted]

yes i'm impatient too but they're fulica eggs, a few will probably hatch. just leave them.

[ian]

Ok im going to leave them im not even going to look.