I found an interesting site written by a vet that has some great info of interest to us all re budgies and cockatiels on this page. If you go to their home page there's lots more of interest too http://www.exoticpetvet.net/avian/budgietiel.html

Thanks budgiebird, always like reading new literature, even if there is repetious stuff, every article has it's own merits and perspectives on things. One can never learn enough, that's for sure!

thank you