Hello gfp,
I am always hunting in the water with either the df, ss, or excal. Waikiki is a very tight and compact area and gets hunted 24-7. So It's all about timing. I would bring the df so you can hunt in both environments. Depth is not really an issue because everything is scooped up daily. Certain areas of Waikiki do have lots of iron including lava rocks which signal loud and clear with any p.i. detector. During the summer months that side of the island can be rough and have high surf so there may be cuts and banks to work. I can't tell you much more than that. I hunt there at least 2 days a week and it's just hit and miss. Keep in touch and maybe we can meet up for a hunt.
I am always hunting in the water with either the df, ss, or excal. Waikiki is a very tight and compact area and gets hunted 24-7. So It's all about timing. I would bring the df so you can hunt in both environments. Depth is not really an issue because everything is scooped up daily. Certain areas of Waikiki do have lots of iron including lava rocks which signal loud and clear with any p.i. detector. During the summer months that side of the island can be rough and have high surf so there may be cuts and banks to work. I can't tell you much more than that. I hunt there at least 2 days a week and it's just hit and miss. Keep in touch and maybe we can meet up for a hunt.