I have always had an aquarium for as long as I can remember (ever since I was little, though then I guess my parents probably took care of it for me, of course) and I always found fish interesting to watch, and now I like the challege of trying to set up and maintain a successful aquarium. I find it fascinating to learn about the different species, and how to take care of them, and the other challeges that come with keeping aquariums (well, some of them I could do without!).
My main regret is mostly my early days of fish keeping. Most of what I knew (or, thought I knew) about fishkeeping was told to me by my parents, who gave very bad advice. I lived by the one-inch rule, and by the idea that fish grew to the size of thier aquarium. I never really thought about fish growing- I assumed that the size they were in the store was as big as they would get. I also thought that every fishtank was supposed to have an algae eater in it, which was either a common plec or a sailfin plec. I had a ten gallon, and always had a pleco in it. When one died, I replaced it with another. I also didn't know much about fish compatibility. I followed the advice of the person selling me the fish, which, more often than not, I was buying the fish from Wal-Mart. At one point I had a pleco, a honey gourami, a 3 spot gourami, 2 guppies, and 2 female bettas in my 10 gallon. At another point I had 3 angelfish in it, probably with a pleco, some liverbearers, and some danios, but the angelfish died shortly after I got them. Thats how I set up my tank- trial and error. If one fish lived a long time (which meant a few months or so), I would replace it when it died becasue I figured it was a success. If it died shortly after I got it, I would get something else.
I feel terrible for the fish that I killed, but at the time I thought I was doing it right- I was following the advice of the people who sold the fish, because I thought they would know better than anyone. I am very glad that I found this forum and now know better.