Go from the aquarium, reconsider any trip to Glouchester (sp?) simply to whale watch - my experience was, as has been mentioned, the boats all end up in the same general area of water. We saw multiple whales in September, and while none breached completely, we did get nice views, some of which were even next to the boat. Additionally, the hour trip out and back offer nice views of the city and surrounding islands. Bring a jacket/cap/hat, it gets windy and cool/cold.