For babies less than 1 yo, u might want to consider letting them swim in thermal pool. There are also places to let babies learn or bond with parents like happy fish at http://www.swimminglessons.com.sg/infantaquatics.htm?gclid=CPfujvuq0s8CFRKVaAod2gcDZg, or little splashes.
Otherwise, in normal pool, babies are best not soaked for more than 20 mins. Floats can be bought at jiffy palace, toyarus etc.
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