Well - it says in the MMII that they are at least 10% larger than the largest giant squid (which are how large?). The Monstrous Compendium is more specific, giving 60' for giant squid and 90' for kraken, but... that is HUGE (and recent research seems to favor giant squids about the size that I made them).
But anyway... Yeah, I like having "mundane" creatures as well as fantastic ones around.

You have also started me on a "arctic/subarctic" mood, to go along with my "aquatic" preference...