When I first had a fish tank, I think I went through about a fish a week. I have a post in this thread if you want to read a thorough explanation:
My biggest regret of all was also in getting 3 small pea puffer fish to eat the snails that had taken over the tank. They nipped the tails off everything they could sneak up on. Wow!! At least they lived. Lol
www.fishforums.net
Please don't whale on me I was a 9 year old kid who was excited about fish
The only thing I did to properly care for them was daily feedings and a yearly water change. The longest fish I had kept lived to be around like 5 years(by my friend's approximation who I gave it to after we moved). It's only now that I'm getting worried about fish, and it seems my parents aren't too happy about that because they want me to focus on my studies. Anyway, now that I'm doing this, I'm going to
thoroughly educate any friends of mine who will keep fish.