A tale of three buckets
So I have three buckets of different grapes for trying to make a red wine. The grapes are from different Vines, but all were ripe and have about 10% abv of potential alcohol. I added about 1 gram of sulfite to every bucket and added some nutrient after crushing. I took my usual red wine yeast and let it sit in sugary water for a day while covered. Then added to all three buckets and put the lid loosely on top.
The first bucket started fermenting nicely after about a day with the peels being pushed up (I push them down every day with a sanitized ladel).
The second bucket didn't start after 72 hours so I added more yeast. Nothing. Then took some Juice from bucket 1 and 2 and mixed and added yeast to that and poured back into 2. It has started now after 5 days after crushing but has a layer of pellicle.
Bucket three has resisted all attempts so far. I tried the same as with number 2 but to no avail. The air of bucket three stings in the nose a bit. The taste is fine if slightly sour (put not much more than the others).
Could there be too much sulfite in the batches still? Bucket 3 was treated with sulfur against mildew about two months ago, could that be the issue? How can I get fermentation started. I can't measure pH but sugar content in 1 and 2 is dropping but 3 is the same .
Also do I need to do anything about the pellicle in 2?
Thanks so much for the help.