i just brought a cockatiel home and my budgies and my cockatiels cages are next to each other i showered the new birds but my budgies are like iching and like grooming each other badly cna u tell me the casue of that????????????????

1st congrats on your new addition

 

2nd it doesn't sound like you did any type of quarantine, so if the cockatiel had mites or anything sickness that is not showing up your budgies can get it even if they are not in the same cages. So I would quarantine now, for the next 30 days, keeping them in separate rooms. This also give you time to bond with your new bird.

 

3rd they could be nervous with this new bird, and most likely comforting themselves through preening each other.