I know how pricey Atlantis can be, but check out Comfort Suites, right next door.... See if they have day passes. If not, you could ask if you could book one night there, and use it as a day pass. It might be within your budget, and get to use all Atlantis has to offer. Sandals, is another option for the day...Beaches, might have one there as well, which is more family orientated.
Below is from their website.
The Comfort Suites® Paradise Island is located adjacent to the Atlantis Paradise Island and guests of the hotel can enjoy full use of all their facilities, including swimming pools, private beach, magnificent waterscapes, Lazy River Ride, water slides, health spa, tennis, and Kids Camp. Guests also have full signing privileges at Atlantis' restaurants and lounges.
Trip, with her book & tea!
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