"Have you tried another strobe configuration?"
You mean configuration (the flash model / size of the arms) or position of the flashes in this series of photos?
The picture was made with two flashes, one on the right side and one on the left.
Were placed to illuminate one the anemone and other the anemone fish.
I also do not like the shadow, but in this situation and angle (from the top) it is difficult to eliminate it, because we are talking about a wide angle lens (fisheye) and a wide area of photography to illuminate and photograph, although in use simultaneously the duplicator Kenko .
