Vacation Feeding

Hi,

I am going on vacation for about six weeks, and trying to figure out a
way to feed my five goldfish (2"-3") in a 55 gallon tank running one
Emperor 400 and one Emperor 280 filters. This is the first time I
will be away for this long. I have asked a friend to look after my
fish, but the best he can do is to come by once every two weeks. I
currently have a Eheim feeder, but it doesn't work very well. My fish
only eat flakes (I tried palettes, but it just accumulates on the
aquarium floor), and the feeder seems have problem dispensing flake
food. So, here are my questions:

1. Can anyone recommend a good feeder that can possibly feed for two
weeks on one fill?

2. Should I be using any of the white pyramid things?

I will be running the light and filter using a UPS. I would
appreciate any other comments and suggestions.

Thanks in advance.

Ashi