oly5050 is right on. Especially in Hawaii it is so expensive to live here. Instructors are not well paid. We do it because we love to share our passion with others. If you had a good time and you thought the instructor did a good job a nice tip would be what oly wrote. If you think they didnt do a good job you should not tip and probably share your feelings with the dive shop. Hawaii is a great place to do open water, but for most of us we live on the tips. You would tip a waiter who brings out the food, you should tip an instructor who has your safety in mind and works hard to make sure you become a safe diver.
viajerochevere DMing on a boat day after day is not as easy as it sounds. Divers lives are in your hands and not all divers come capable. Not to mention the ones that are "experienced" divers and demand they need 30 pounds of lead even though they are in a shorty and weigh 150 pounds. or they... everything you can imagine and you are responsible for safety. sometimes abrasive people who you are just trying to keep them safe and they just want to be "right". And that is just the diving not to mention all the prep and gear cleaning, boat cleaning, loading unloading tanks, 2- 5 dives a day. up at 5 am back home at 11pm. then back up at 5...
dont get me wrong i love teaching scuba, but it is harder than you might think.
fatdiver where in Hawaii are you coming to?
Aloha