Here's the picture of the sac when the mother still there. Now it's have some black dot appeared inside. In my place the celcius is around 13°c to 18°c can they survive or do they need warmer condition
She would have needed air too. Did you keep it in a drinking glass?
Temperature is fine... Any way to see what the black dots look like ?
For sure as you can see the spikes on the egg sack.
My brown widow was making a new egg sack every other week for about two month. I had no intention of keeping them so I put them in a separate container with tiny holes in the lid to see if they would hatch. About two weeks after I put the first one in there I tore open the sack and about half the eggs fell out. A few days later I had eggs with legs and now I have tiny almost brown spiderlings. I also have several more egg sacks in there that I haven’t opened. I have no idea what to do with the spiders. LoL. My point is that you could try opening the sack to see what the eggs look like and the little ones will be fine. Just wait two weeks after the sack was created. If there all bad maybe I can mail you a few.