I have some kelp powder (actually, it's kelp, flax seed, and cranberries) that I got for the cats months ago, but just now opened. Is this safe to add to food made with Alnutrin, and if it is, should I leave out the green-lipped mussel? I got it because it's supposed to be good for cats with urinary tract issues, which I don't anticipate having again, anyway, with them on raw, but I would like to use it if it is safe for them.