Cider 10-19 update

I lost a gallon of cider. I had been keeping the cider in a cooler with ice and I think this particular jug was more out of the water bath than the others. It was also touching against the cooler on the bottom and the side. I might let it ferment and then try to make cider vinegar. I found a 4.4 cubic-foot refrigerator on Craigslist. I’m not sure how cold it will get, but the remaining four gallons of cider are now in it. A 6 gallon brew bucket, 5 gallon carboy, and a keg will fit in it individually. I need to decide on a specific gravity for the cider batch. How to achieve it. Fermentations carries White Labs Yeast and I’m using the WLP775 English Cider Yeast in this batch. The recommended temperatures for the cider is between 70F and 75F. Trader Joe’s carries some apple juice so I will try to find a gallon to add to this batch. The Everything Hard Cider book recommends their Gravenstein Juice but alas they didn’t have it when I checked on Sunday. I’m going to boil a pint of water and then mix some yeast nutrient, let it cool and add it to the cider.