Missing a meal one day is not a problem for fish. They can go at least a week, and I know some on this board who have been unable to feed fish for 2 weeks without a problem. I generally skip a day feeding about once a week. I think the benefits of feeding a varied diet far outweigh any skirmishes over the veggie. I cut mine in long strips, so several fish can get at a section. The plecos chow down overnight. Don't leave it in for longer than 24 hours, though, because it starts to break down and mucks up the tank. My little daughters are so impressed that the fish like to eat veggies!