Jozlyn at the end of the day it's up to you, can only go off my personal experience with livebearer fry as they were in a 8 gal bow front tank, and I had to do water changes a couple of time a week.
What's a "rubbermaid" container?A 10 liter is about 2.5 gallons, same as I use for cory fry. Anything I have ever bred gets fed 3 times daily, I'm not about to quit my day job to feed fish.
A fry tank doesn't have to be a tank, many have gotten by with rubbermaid containers for fry tanks.