Sorry, I don't know if that's a kelp that Moreless would recommend to use or not. I know he has recommended kelp from here: http://www.seaveg.com/
Which is where I bought my kelp. I bought 6 lbs of it and the company told me not to freeze it, but to store it in a cool dry place. They also told me it should last a good couple of years. I have also used this kelp for the garden as well.
Sorry, I'm not sure about the plastic jug question.
Good luck with the drink...let us know how it goes for you.