NOTE: This is a freshwater water chemistry talk. Mike Wickham's Bio: Mike Wickham has been a hobbyist since 1964 and was an aquarium retailer for 25 years. He wrote for Aquarium Fish International magazine for over 20 years, including 10 years as the â€œFreshwater Q&Aâ€ columnist. Mike has also written for Aquarium USA, and Pet Product News magazines and is the author of several aquarium books, including The Complete Idiot's Guide to Freshwater Aquariums. He currently serves on the board of the Northwest Arkansas Aquarium Society.