First of all, as others have said you are way overstocked and a new tank is in order. As long as you are thinking about getting a bigger tank, the bigger the better in this case. I have a 125 for 5 large cichlids and I think that is pushing it sometimes because of aggression and territory issues. After all, compared to the wild where thier room is limitless this is just a big glass box and they can only go so far to get away from the aggressor.
Next, PLEASE do not ever use vacation feeders especially in such a small tank. They always pollute your tank in a very big way and they are amess to clean up after not to mention very sad when it kills all of your fish. If you are only going to be gone for a few days the fish will be fine without any food. They do not need to eat everyday like we do. They can actually go for weeks with no food. If and when you have to leave again(and you will because that is the way life is) I would do a water change before you leave and feed then normally right before you walk out the door. They will be fine while you are gone as long as the filters and heaters and such are working.
So if you can, try to get the biggest tank you can reasonably afford and take care of. Just keep in mind that bigger tanks need bigger filters and heaters and the like but are usually easier to take care of because bigger tanks means more water volume and they are way more forgiving of mistakes that we make.
Good luck and keep us updated on the progress of your tank.
Marinemom