Branches - I change the branches in the aviary about every two to three weeks. They love apple branches when I can get them but have sycamore branches most of the time. If you can stand the mess - leave the leaves and buds on - they have a great time with them. Wash any branch first though - just to make sure there isn’t a swan stuck on it - and check its not privet or a plum branch!
Cage - here you simply need to get the biggest cage you can afford that will fit in your room. Try to get one where the bars aren’t too far apart (about 19mm is good) and where the bars on some of the cage run horizontally. I’ve read that you should avoid round cages if you can but never really looked at them myself.
Perches - To keep their feet healthy cockatiels need to exercise them by gripping perches of different sizes. You’ll be surprised how thin a branch they can climb along - if there’s a tasty bit at the end! They tend to perch as high up in the cage as they can get.
In the aviary I’ve got plastic perches, long wooden dowel perches and also a concrete perch - all of these vary in diameters and with swings and other things keep them happy.
Sandpaper - I don’t use sandpaper in the aviary at all. I find that with the concrete perch and the natural branches the cockatiels keep their nails in trim.
Toys - I have a few homemade toys and also some bought ones - I swap them around every few weeks to let the birds have a change - which they seem to like. String, wool and beads are a favourite - make sure the beads aren’t too small and the string too long.
