Hey,
I just returned to the U.S. last night after 2 months in Asia; so I have some recent experience with being away from my fish.
While I was gone I arranged for my neighbor (with no fish knowledge) to feed the fish, a pair of dempseys, a firemouth, an angel, and various others. I instructed 1 feeding every other day for 2 months. 2 months and zero water changes later they are thin (not starved) but are acting and looking very healthy. Instructing underfeeding for such a long period of time has had no apparent ill-effects. I am uncertain of what the long-term effects may be, but I am sure that underfeeding was better than the alternative, overfeeding.
In the past when leaving the fish for only a week or so I have always left them completely unfed. Before I had automatic light switches I left the tanks unlit as well. A few times I left my fully grown Oscar unfed for up two weeks while I was away from home, and he was always fine. I think your fish will be fine.