SEA LIFE Bangkok Ocean World boasts the biggest aquarium in South East Asia (unless you count the Pacific!). It's easy to reach by public transport from Bangkok, just take the BTS to Siam Station, or one of several buses heading in the direction.
Siam Amazing Park is an amusement and water park in the Khan Na Yao District of Bangkok, Thailand. It was founded in November 1980 and remains the oldest amusement and water park complex in Southeast Asia.
Vana Nava Water Jungle is Asia’s first jungle-hemed water park. Located in Thailand’s beloved resort town of Hua Hin, this ecologically aware, community water park combines state-of-the-art technology, modern facilities, and over 20 rides, slides, and attractions. It's also home to Thailand’s first professional underwater studio.