StillSmart

Decided to split difference and run 3 pouches for 28 kg which is around the upper limit on the pack so far so good
BTW creative wine making are doing a BOGOF ie 2 packs for £3.99

If you cut down to 5 or at most 6 kg's of sugar per 25 litres you'll be fine with most yeast/nutrient combos and one packet will easily do 50 litres. I personally would vote for vodka star out of the alcotec options.