Hakkeijima Sea Paradise - Zoorasia

No, since it'll take you about 1 - 1.5 hours from Shinjuku to Hakeijima Sea Paradise alone, a little less than 2 hours to get to Zoorasia, and then another 2 hours to get back to Shinjuku. And as Hakeijima is a large aquarium and a theme park put together, I think you'll have more fun spending the whole day there, than trying to fit both places into one day.