Since I kinda have a Mouse problem im worried something might happen to the chicks so I was thinking how about changing the Cockatiels room to a bird room and attach the nest box to the wall so its up nice and high.Is this a good idea? I was planning on hanging Toys,Swings and ladders from the ceiling anyway but the nest box is an added idea.Any opinions/suggestions?

That would probably keep the mice out of the nestbox. Be sure that the mice can't use the ropes and ladders to climb up high. But as long as you've got mice running around in the room at night, it's quite possible that the birds won't want to nest. They'll hear what's going on and it won't make them feel secure.

You also have to consider what could happen to the adult birds during night frights. My guys have a whole room to play in during the day, but at bedtime they go into cages for their own safety, so I don't have to worry about them crashing into a wall at full speed during the night. The hen normally stays in the nestbox at night (at least while the chicks are small) but if something scares her she'll come out of the nestbox and try to fly. It'll be safer if you put the nestbox in a cage or some kind of enclosure so she can't build up too much speed.

Please consider getting rid of the mice before you breed. The mice are just limiting you and will mess your birds from breeding.

We already put mouse poison down and lots of it was eaten so the mouses will drop dead.The ladders and stuff would be hanged high so like you have to fly to get to it.

Well the fact that the mice could get in the cage in the first place shows that they have a pretty good climbing ability. Best wait until they're all gone before breeding, just to be safe. You never know what could happen.

That is what im doing I wasn't planning on breeding until another 2 weeks anyway.

Clear the mice first. takes weeks before you can be sure they have all gone... oh, and mice can climb, get into spaces the size of a round pencil hole...also they can scale walls.

Obviously lol