100 mm macro + magnifying lens is the way to go at the Wall if you want to catch something, and don't forget the light. I was very short of everything with my 50mm which refused to focus neatly on the yet difficult to spot critters, here a hardly noticed hingebeak translucid shrimp.

From that night, I promised to myself to invest soon into a video light.
Note to myself : add to shopping basket with dome, ultrawide lens, 100mm macro and second flash...ouch...