"Which lenses are ideal for underwater photography?"
"The closer you are - as better your images are!". Objects which are further away from you than your extended arm you shouldn´t even try to photograph (except uw-landscapes) - that is the rule of thumb. Water is not air, contains a vastness of particles which lead to scattering, deflection and reflection. In addition, the photographically useable image distance is only on third of the eye´s optical range. Due to this, for underwater photography mostly lenses that can be adjusted very close are ideal. Lenses with minimal adjustable closeness range of 15-25cm are ideally suitable. Constant focal lenses are better suited than zoom lenses. Therefore a macro, wide lens and fisheye lens should belong to the basic configuration of each ambitious underwater photographer.