Despite the fact that the waters of the Maldives are relatively warm, generally a wetsuit will be helpful for a comfortable dive. Usually, a suit of 3 mm will be sufficient, but if you desire to descend into significant depths or to dive a number of times each day, a 5 mm suit will be preferable. On the other hand, it is not impossible to dive wearing just a T-shirt so long as you do not mind the cold.