in the future if your gone for a long period of time, you could consider getting an auto feeder. ive never had one but they do seem cool.
Nope, those are a bad idea. I had one when I first started keeping fish, and it dumped my entire container of food into the tank while I was gone. Result? All fish died from the terrible conditions. This is also because they are made to feed twice a day or more. Personally, fasting would be the way I'd do it. If you're really concerned next time you go for a week, you could have someone come feed them on the 5th day. But if they were fine before, then they'll be fine again.