I would suggest getting another tub they'll settle down quicker on their own. Balls are not known for liking company unless its of the opposite gender.
Pick up another hide and water bowl for the other tub while at it too. I'd leave them separate in the tubs for 3 weeks maybe a month to adjust to the new surroundings and decent meal in their belly.
Feeding wise, give them about a week to settle in then offer food, can try frozen/thawed first and you can leave it in the tubs with them over night. Make sure you have a snap on lid too, they will try to climb out through the top, my own 3 ft does this easily.
A small drill bit will punch a few holes through tubs easily just make sure you're doing them from the inside out, so the rough spots are on the outside of the tub. If you're worried about the room getting a bit too cool for the night you can used a human heating pad on low to give them a bit warmer spot and its less likely to burn the plastic tub or your floors. Do note that most of these shut off after about 6-8 hours.

I think I hit everything you asked. lol