I'm trying to make some at present but can't get it to carbonate. I've tried twice with my long established ginger bug which has been working just fine for making ginger beer for months now but for some reason it will not work with this lemonade. I have even tried a third time using some whey but still no luck. Is it possible that the mix is too acidic (I juiced two lemons and one lime for a two litre bottle). Any help would be appreciated.