Thank you very much for the quick and efficient replies. I certainly could use your assistance and knowledge. I might need a tour guide. :) Happy diving. Who knows maybe we will dive together someday. I teach science and take kids snorkeling in Florida and many go on to be certified divers. I am actually teaching about the oceans this week and next. We will learn about bioluminecence and other fascinating subject matter. We will also do labs on bioluminescence and chemiluminecence. Take care!