I did feel a bit like I was being attacked for using the Frog even though I've never had any problems. My pool person (a friend who installs and has one himself) set me up with it and it's worked great for 7 years. This year, my only problem was initially not getting any FC reading and now that I have my Taylor test kit, I'm seeing that my CC is higher than my FC and I attempting to correct that. Various people on this forum started talking about copper in my water but I have verified my copper test is showing no copper and we've NEVER had green hair. So, I did ask King Technology about the copper and they told me there was no copper but by using the mineral pack (which includes silver and limestone) I am able to operate at chlorine levels of 0.5 to 1 ppm but that if I removed the mineral reservoir then I need to do at least 3 ppm. So, I'd like to just resolve my 1.0 ppm CC problem and then worry about algaecide and copper and all that other stuff later. I thank you for all your research into that issue. I saw bucket test directions on this forum somewhere but cannot locate them now. Is there a link?