Let's see, an estimated ten million species of which perhaps two million are non-insects. Considering space for food and the water needed for all the marine species, at only 20 square feet (that is a 4X5 area) on average for the non-insects alone that would 40 million square feet plus the space for the bugs. So, perhaps something 14 times the size of Cowboy Stadiums (which has 3 million square feet). Or, over 4000 times the estimated 100,000 square feet of a tri-level Noah's ark. And I'm guessing that my estimate is on the low side.