Priming questions.

I have a couple of questions about priming I hope you can answer for me.

I did a run of bottles and primed in the bottles (I now know it's a lot better to prime in the bucket) One batch (Pale Ale) turned out fine, posibbly a little active, but that should settle doen when chilled) The other (Cider) was still flat after 1 week, I'll give it another week or two.

I've read that if it does fail you can open, reprime and cap again.
My main question is can you ever run out of yeast in the beer so there is nothing to work on the sugar? Is it ever worth mixing more yeast with the priming sugar, if so How much.

My next question is about the amount of priming sugar. I've read quite a few articles and it's all based on volume of co2 for temp and ale style etc.

Is there and simple way to do it. I've seen one article that says for normal sugar it is one teaspoon per pint and increase by 25% if DME is used.

Any suggestions please.

I always premix. Good avg for carbonation without having to chill the beer before opening is 3/4 cup corn sugar or 1 1/4 cup DME for 5 US gallons.

There should be enough yeast in there to do the job. What temp are your bottles stored at? Sometimes they like a little warmth for the 1st day or two. I usually have mine around 22-24 deg Cel. (70-75 F?) then move to somewhere colder for conditioning.

I will be keeping them at around 70f for 2 weeks then maybe a bit cooler and I'll chill befor drinking.

Cheers.

My Fool's Gold Ale came out with very minimal carbonation, so I decided I'd try uncapping, chucking in a bit more corn sugar, and recapping.

I tried it with three bottles, and each volcanoed (foamed everywhere and spilled out of bottle) before I could get a new cap on it.

I'm just going to drink it as it is...