The service is great. The instructors use swim rings to guide everyone in the water, which is excellent for those who aren't strong swimmers. They carefully count heads throughout the entire experience, making it feel very safe. Although the instructors speak Japanese or English, they use simple terms that are easy to understand. They also offer basic photography services. The only downside is that one instructor seemed to treat Japanese guests differently from those of other nationalities, but it wasn't unbearable.