My other concern is giving the tank itself time to adjust to the bio load. I'm probably worrying a bit too much. I have some floating plants in the quarantine tank so that should be fine.I usually wait until the following morning to feed, just because new fish tend to be a bit too stunned to eat much right away. If they're actively foraging and telling me they're hungry, I might feed them after an hour or two. But I don't want a bunch of food rotting in the tank, so I wait until they're acting hungry.