Hi Everyone, My interest in your website came through my ill health. I bought a ph pen through a website in Johannesburg in order to test my ph so I can keep it at 7.4 in order to improve my health. The problem arose when I need to buy calibrating fluid and had no idea how to set about it, so I went on the web and the only help I could find was through your website. For which I really thank you. It has not been an "accident" that I arrived here. I have always been fascinated with sea creatures and indoor aquariums. So, if you don't mind, I would like to remain a member.