This one is a MUST if shore diving the Big Island. There is much written here so I would just add there are actually two ALOHA cement brick structures. The first is just to the right of center as you head straight away from the entry. 30' (or 10 meters) sounds about right for the depth. If you go just a ways past it, the depth drops off and you can swim north along a sloping wall of coral at about 60-70' depth until you hit 1/2 tank (beyond that I don't know). If you head south instead, the depth increases until you come to the 2nd ALOHA which is larger and located on the sandy bottom, probably more like 30-35 meters of depth. It either took a few divers several dives to put it together, or a whole team of folks who could have built it in a dive or two. (I gotta get a UW camera for these things!) Enjoy!!!