A bad hobbyist is someone who refuses to provide clean water conditions for their fish. (and there is such a thing as a bad hobbyist)..but I never named names..so don't take it personally, please. An effective way to make sure the water is "healthy", is to do water changes and monitor your levels accordingly...and as I said, if a person can't or won't change the water enough to acheive these levels, then they should use the products to insure that their water is healthy. IMO, a "bad hobbyist" would do "nothing" at all...no water changes or chemi-pure..I never said that any of these products were worthless, or snake-oil for that matter...I think they do work to a very good degree(especially in salt water aquaria)...but my point was, they are redundant in fish tanks that are already well maintained, and the fact that regular water changes will produce the same results that these products claim to acheive. All I offer at these forums is my opinion, which is formed from my experience as a fish keeper. I have used many "products" over the years, and found none to be more effective than a good old fashioned water change.