Don't use 2 packs! I did just that with a recent brew, against my lifelong practise of using just 1and ended up with the most horrendously cloudy ale in the bottles. Gonna end up with 3mm sediment in these. Wasn't prepared for a plan B like transferring to secondary etc... I'd already got the bottles sterilised etc etc. Gonna put it down to experience and stick to the tried and tested 1 pack - there is simply no need whatsoever to use more. And it's a pack wasted grrrr.