I agree, Cheese. Unfortunately, home aquarist is not an exact science. We learn by trial, error, and getting by with a little help from knowledgeable friends.
Just like parenting, they do not come with instruction manuals.
Each fish (or child in my comparison here) is unique. I have one goldfish who tolerates nothing by a pristine tank and unmoved objects, while another loves his tank rearranged and swims into my hand for loves while I rearrange for him. I know most people would freak if they heard that...but the SALT keeps his slime coat and electrolights in order, and him very happy and tubby wubbed. (tummy rubbed, LOL)