I can suggest finding your way to Mismaloya and hire a private guide. We asked for Isreal. He was great. My wife was a first time snorkler and he got her going, she loved it. Unbelievable bright colours of the many fish around Los Arcos. The cost for 4 of us was 300 Pesos an hour. We snorkled for the first hour then went on a tour for the second. We enjoy this privately guided trip.