Scuba diving resorts will never allow you to go diving without certification from any of the agencies mentioned. This is because scuba diving can be dangerous if you don t know anything about it. For instance, you need to know about underwater pressure and how to cope with it. The pressure itself can be dangerous if you don t know how to equalize. For example, if you are certified as an open water diver, you are only allowed to dive in dive sites that have a minimum requirement of open water diver. However, if you are certified as an advanced open water diver, you can dive at dive sites that have a minimum certification level of open water and advanced open water. This is because tempered glass is less likely to shatter into fine, hazardous slivers. Another feature you should look for is that it should have a comfortable skirt with a close fit to your face and provides a good seal. A mask should also have an adjustable strap that can be locked in place. You should always remember that scuba diving is a relaxing and fun activity, choosing the wrong scuba mask will make it uncomfortable and annoying. This is the best place to go if you want to see grouper, snapper, schools of jacks, sharks, manta rays and as well as other tropical marine species. Brightly colored fishes can be seen in these islands. There are also ship wrecks that you can explore in the Caribbean coast. The wreck is called the Fenix. Typically, it varies on the kind of service they have and on the number of vacationers. You can choose from either signing up for an escorted group or plan the trip by yourself. There are also travel agents who are willing to render their service before you. They can help you and inform you regarding the diving packages that are catered by the resort. Scuba tanks are often filled with air, similar to what we breathe on the surface, that are compressed to about 250 bar or 3000 pounds per square inch. Sometimes, scuba tanks are filled with special mixtures for special diving. You can also have a tank filled with NITROX that will enable a diver to have longer bottom time but shallower dives.