Hm, from my experience taking care about the food cultures by the family is much bigger problem than taking care for the fish. So what I do is that I reduce the cultures heavily before I leave home and transfer them to maintanance mode with lower temperatures and make my family feed only very lightly and every other day. This is done with both moina and rotifera cultures If I currently keep some. Feeding and maintaining high density cultures by the family always resulted in disaster for me 🙁 By now I keep fresh water Rotifera eggs that allow me to always start a new culture and I have Moina on the garden so I only run indoor cultures during freezing periods of winter. Probably starting a garden culture of Moina would work for you to, just make a small pond or use a big barrel or something, put in there some leaves or couple handfulls of grass and leave it alone. This way you should be always able to renew your culture or even collect some Moina for the week to come.
As for the feeding for periods of two weeks, I would just use brine shrimp, its the easiest way and there is no harm to be done.
Hope that helps.