Ahh, I see you've visited mytoos dot com! LOL! They have some very valid points, there, but I've also found some of their people to be rather unpleasant and lacking in diplomacy skills. Cockatoos are the highest-maintenance of most of the parrot species (CAGs are right up there, too), and the Moluccans and Umbrellas are the highest maintenance of them all! Since most 'toos are cuddled to extreme as babies, they tend to get used to that, and when/if that level of attention wanes over time, they can become unhappy and act out with behaviors such as non-stop screaming, toy banging, biting (and 'too bites HURT--they have the equivalent of 2 very sharp "fangs" on their lower beak), and plucking or mutilating. These problems are the reason that cockatoos are the most rehomed parrots out there.
Cockatoos need less fat in their diets than macaws and other parrots. Too much can lead to fatty liver disease and other problems. Therefore, keep the nuts for a U2 to between 3 and 5 a day. Preferably in-shell, so they can enjoy taking them apart. It's part of the fun

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There are some good parrot foods out there. My favs are Sunscription Vita Parrot and Volkman Parrot. They are clean, and my birds (macaws--who get the Sunscription Vita Macaw and the Volkman Fruit and Nut Goodies as their base seed mix) go ape for them

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From the home, give them fresh organic fruits and vegetables. Favorites are grapes and often bananas, as well as pomegranate (if you can stand the mess and stains the seeds make), mango, and papaya. They usually adore string beans and peas in the pod, as well as things like kale, spinach and carrots. Avoid onions and garlic. These items cause the blood cells to actually burst in 'toos and Macaws (and probably other parrots, too). Also avoid the obvious things--sugary drinks and candy, caffeine, chocolate, avocados, and many of your houseplants. Make sure everything is washed prior to feeding, and I recommend not getting grapes from Chile, where they still use DDT as an insecticide. Around here, that means usually my birds only get them seasonally, as during the off-season, most grapes come from Chile, at least in our stores.
Most parrots love legumes (cooked to "al dente", not "mushy"), squash, yams, potatoes, breads, cereals, grains, and the occasional bit of protein in the form of chicken, scrambled eggs, or even a little bit of beef or pork. They can also eat pellets, but I don't like it as a staple diet for a high-maintenance, intelligent birds. A bored 'too is an unhappy too!
If you've only had your U2 for a day, be prepared for a "honeymoon" period. Rest assured that'll change when the bird starts feeling comfortable in your home. Depending on the individual bird and the environment it came from, you could get anything from a screamer to a plucker to a biter--or not!
There are 2 big keys to successfully keeping cockatoos, ime (I've had a M2 and a U2 in the past). Keep them BUSY, and teach them to entertain themselves independently from your attention. Cockatoos are SMART. Most of them are very mechanical, and love taking things apart and putting them back together again. There are any number of interactive parrot toys on the market that would be appropriate for them. There are also a lot of good parrot forums out there, of which Avian Nation is one of my top picks. There are some amazing experts, there. Look up Lara if you go. She has a LOT of experience successfully maintaining her 'toos, and they thrive in her care.
Teach them to be independent by slowly transitioning from more attention to less. Do NOT do it suddenly! You'll regret it if you do--I promise. While you're doing this, give them lots of things to do--destruction toys, foraging toys, interactive toys. Whatever will keep their minds and bodies busy for a length of time. If you have an aviary, they often enjoy spending time outdoors in them, watching the world go by. Just remember that they'll call or warn the world about what they see--and do it loudly. Your neighbors probably won't appreciate it, so you might consider doing what we do with our macaws during good weather--put them outside after 10 am, and bring them back inside by 4 pm, weekdays only. It works for us, at least.
Do you know the bird's gender? If it's female, you'll want to avoid petting it under its wings or along its back. At her age (if it's a "her"), she'll find that sexually stimulating, leading to frustration on her part, and perhaps even chronic egg-laying and possible egg-binding. Keep nesting places (boxes, etc) out of her cage. If it's a male, watch for seasonal aggression.
Provide dust baths (similar as for chinchillas) or showers (we use a mister) for your 'too frequently. One, it keeps the feathers nice and clean, and 2, it keeps their dust down. They are known as "dusty" birds because of their down, which is meant to be an aid in grooming, so it breaks down into a very fine dust as they preen themselves. This dust sticks to absolutely EVERYTHING. It's rather like talcum powder. It sticks, and it's hard to get off. Breathing it can be dangerous to your health, especially if you have respiratory problems to start with, so I suggest a hepa filter in their living area. I also suggest that you do NOT put the bird's living area in your bedroom! You really don't need to be breathing that dust in all night long. Ask long term 'too (and Grey, and Cockatiel) keepers--you do NOT want to develop birdkeeper's lung!
Watch the bird's crest. It will come up when it's angry, frightened, or excited. Learn to read which of those emotions you're seeing, and act accordingly, which mostly means avoiding the beak! An excited or angry 'too is more inclined to bite, and remember, you don't want that

. A frightened 'too will usually scream and display. Don't push it--it can lead to several outcomes, most of them not good for you or the bird.
'Toos can talk, but they don't generally talk as well as, say, Greys or Amazons. Still, they can learn to have conversations. So watch what you say around it. They, like macaws, are drama queens, and the louder and more animated you are when you're talking, the more likely they'll pick up whatever you say. Cussing like a sailor probably isn't a good idea, especially since there may come a day when you'll need to rehome it. It's harder to rehome a bird that uses bad language!
If it starts to pluck, I suggest contacting a behaviorist (like Lara at Avian Nation). They can help you discover what the problem might be, as well as some suggestions to help diminish or extinguish the behavior. They'll also be able to help you decide if a certain behavior may be caused by a medical problem that needs seeing by an experienced Avian Veterinarian. Mutilation is a serious, life-threatening problem, and fairly common in unhappy or sick cockatoos, and this ALWAYS needs seeing by an AV for diagnosis and treatment of the wound, as well as working with a behaviorist if you're interested in your bird's physical AND emotional/mental health.
That's all I can think of off the top of my head. I hope it's helpful. Cockatoos are a LOT of fun, but they're also a LOT of work! If you decide to keep this bird, be sure you're ready for the commitment. They can be well worth it

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