All divers learn to consider the phase of the moon as they plan their dives. For handi-divers, this is especially important. The moon controls our tides and thus, determines tidal surge. The effect of the moon on tides is strongest during both full and new moons. That means every two weeks the tidal surge due to phase of moon will be strongest. Handi-Divers should consider this when scheduling dives. For a moon calendar, you are welcom to visit Paul Carlisle's website.