In terms of aquaria, SeaWorld is funded by United Parks & Resorts, so it would be one of, if not the, most well-funded in the Americas (though how well they use that funding and spread it between parks is more a matter of debate). They also have a truly massive facility in Abu Dhabi which I would wager was the most expensive aquarium ever built at a staggering $1.2 billion USD, and is probably the most well-funded aquarium facility worldwide right now. Disney also does have an aquarium, the Seas with Nemo and Friends, but I don't think the individual funding there comes close to SeaWorld even though they are a larger corporation on the whole. The SEA LIFE facilities by Merlin Parks and Entertainment also should be considered in any assessment of aquarium funding. If you separate the nonprofit facilities, Monterey Bay Aquarium's endowment is truly massive as it's provided by Hewlett-Packard.