Sorry if I missed this in another post, but does anyone know of a shelf life on the DIY? I mix 1000ml at a time, but my mixing containers are 800ml. That 800ml takes me about 2 months to go through. So I have another container that I put the extra 200ml into. after 4 batches, I have an extra full bottle, but some if it is several months old. Is this a bad idea?