Goldfish; The emotional investment

We haven't done well with fish. Every time I buy them, they last long enough to surpass the store warranty and then they die.
About 3 months ago, when we finally started being able to see Christian, we took him to the pet store and bought him 3 cheap goldfish. My thought on this was, if they die, I can just keep replacing them (I can't get this past Jobe anymore. He knows if the fish are different). I've never seen a little boy so excited. He named them Christian, Dean, & Mosely (his full name). 67 cents and we had made a little boy incredibly happy. And when Jobe saw them, he was equally happy.
Let's face it though, fish don't do much, so when you're 5, the only enjoyment you can get from fish, is feeding them. One weekend Jobe started to feed the fish a significant amount and Mike told him "If you overfeed the fish, they'll die." -My kid is pretty sensitive about life. So this phrase sent him into a dramatic spiral that didn't end until the next morning when he came flying into my bed informing me that "THE FISH ARE ALIVE!!"
Mike, feeling bad, decided to take a different approach with Christian. He sat him down and explained how much to give them and how often and why it was important... Throughout the entire 15 minute conversation Christian translated it to "If you overfeed the fish, they'll die."
SO.... Now we have 2 little boys that are afraid to feed the fish at all!