One of the hardest things to produce in TG2 is the "Bottom/Underneath of the Surface" of the water, that though it is transparent, but also reflective bend ing the light as it passes through. When I have tried to see the TG2 water from below the surface, it does not appear because the water is not of a volumn material
I am sure there is a work-a-round, but I have not found it. Also, TG2 has either No or Very Little Caustic response to light on metal or in the water. To just create the scene though would not be that difficult. Thicken the haze to mimic underwater opacity or the relative capacity of matter to obstruct the transmission of radiant light energy. It is very doable!!!