basic care sheet for cockatiels...
Plenty of seed - limit the sunflower seed as it is high in fat. Millet, canary seed, safflower seed, basically a good finch or parakeet mix with a few sunflower seeds mixed in. You can increase the sunflower seeds during cold weather to help them maintain warmth. There are different types of millet seed. White Proso Millet is the basic seed for pretty much all seed mixes. Red millet comes in spray form - basically it is cut off the plant still in its seed head and sold as a millet spray. You can alse get seed sticks. They come in different flavors and sizes. Some have fruit and veggies mixed in also.
Plenty of water - cockatiels are native to Australian grasslands so they may or may not drink a lot of water. Some will bathe in a container of water, some will prefer being misted lightly. Fresh water should always be available.
calcium/minerals - Get a cuttle bone and a mineral block in the cage for them to chew on. Cockatiels actually crack their seed so they do not need grit. Some will eat it anyway, so if you want to put a small dish in, you can. Get the oyster shell grit as it will also add calcium to their diet. Too much grit can cause an impacted crop. Egg shell is another good source of calcium. Either bake it in the oven, or crush it and cook it in with scrambled eggs (and other goodies) as a treat for them. Raw eggshell can carry salmonella bacteria. Wash the eggshells, crunch them and spread on a baking sheet. Bake at 250 degrees farenheit until lightly browned.
Other edibles - Fresh fruits and veggies such as apple, broccoli, cauliflower, oranges, carrots, squash, etc. are all good. Veggies can be fed raw or cooked. Do not give avocado, onion, or garlic. Pastas, beans, and rice are also good. Cheese is okay in small amounts. Scrambled eggs are a good way to sneak all sorts of stuff in your birds diet. You can chop a variety of veggies and crunch some eggshells in with the scrambled egg. If your cockatiel is a bit picky, sprinkle some seed on the fruits or veggies. When the cockatiel picks off the seed, they will get a taste of the other stuff as well. Also, try different ways of preparing the food. Some birds may like chunks of veggies, while other birds may prefer theirs shredded, grated, or mashed. My Rascal (cockatiel I had) used to love to eat spaghetti and scrambled eggs with me. Twitters (the lovebird I just raised) simply adored brussell sprouts. Both of them liked carrot tops with some of the carrot still attached. You can also sprout some birdseed in a small pot and put that in the cage for them to devour. Parsley is a big hit with my finches, and Rascal used to eat it also.
Cage size - The larger the better. The minimum size would be for your cockatiel to be able to fully extend their wings without touching anything else in the cage. If the bird has outside the cage time every day, then they could be in a slightly smaller cage. Depending on where you are and if you want them to be pets or aviary birds, you could set up an outdoor aviary for them. The very most minimum size for one cockatiel should be roughly 24 inches wide, 18 inches front to back, and 24-36 inches tall. If you have two in the same cage, then you may want to consider a larger flight cage. There needs to be room for both birds to stretch their wings out fully at the same time without bumping the walls of the cage or each other. Cockatiels have long tails and a feathered crest on their heads that they will need to have room for.
Wing clipping - Cockatiels are strong fliers. The primary flight feathers are the ones that stick out farthest on each wing. The feathers that need to be clipped are the first 5-8 primary flight feathers clipped back to where the covert feathers cover the base of the flight feathers. You want to make sure you take off enough that the bird cannot fly up, but not so many that they go straight down. The bird should be able to glide down at about a 45 degree angle so they don't crash land. It is fairly simple to clip the wings, but have someone knowledgeable show you the first time. If the birds are not tame, and you do not care about taming them, then getting a larger flight cage or aviary for them and leaving their full wings would allow them to get sufficient exercise by flying inside their cage.
Toys - Cockatiels need to have toys that will entertain them. Bored cockatiels can start picking their own feathers and do major damage to themselves. Toys that can be chewed and shredded are good. Wicker, paper, sisal, etc. are good options. There are also ones with cotton rope that can be preened which are good. Some of the smaller or softer wood toys would be a good option. There are also a variety of hard plastic and acrylic toys which are suitable. Some cockatiels enjoy bells. Stay away from the jingle bell types as the birds beak can get caught in the slots. The cowbell style of bells are a good alternative. Mirrored toys can cause aggression - especially in males. Toys that hold food treats are a good way to keep your bird entertained and provide a variety of treats at the same time. For birds that like to shred everything in sight, cardboard toilet paper or paper towel tubes are a great cheap toy. Cut the tube all down one side so the bird does not get it stuck on their head.
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i haven't had any birds since i was a kid, and back then i didn't know anything about them, but recently i've been looking into it a little more so this is great info for me!
