so long Zeus

In the morning I will have the sad task of letting my kids know that Zeus is gone. We forgot to feed the fish this morning and soon after we came home from a long day away I noticed that Zeus was sinking!! Pete stuck my pen in the bowl and tapped him and he perked up for a second, but he just didn't have the will to survive. The kids were waiting for their bedtime story and I didn't want to break the news right before bed so they will be finding out in the morning. I'm sure Pete will rush out of here before they wake up so that I'll get to be the bearer of bad news. Hopefully Ariel, the smaller of the two fish, will hang on a little longer.
The first couple of days we had them they really weren't eating at all. After about 3 days they started eating, but Zeus never seemed to have a very big appetite. Any advice you all can give me on goldfish would be great. I feel like kind of a loser for not being able to keep a fish alive for a whole week- grrr.