I've done a lot of reading and research into the feeding and proper care of cockatiels.  Because I'm a "stay-at-home-mom", I have the luxury of being able to develop a routine for Pirko which seems to ideally suit his nutritional needs.  If you are considering getting a cockatiel, and wish to know what I've found works for us, well, read on:

Pirko's Diet

  • In the morning, Pirko gets a warm breakfast of Beak Appetit mixed with Zupreem pellets.  His two favorite kinds are "Nuts for Alfredo" and "Cheese Teasers".  I make this up ahead of time according to the package directions, and freeze it into ice cube trays.  Each morning I pop out a cube, put it into the microwave for thirty-five seconds, and then mix it before serving to prevent any hot spots.
  • I remove the Beak Appetit mixture after about an hour and a half to prevent bacteria growth.  At this time, I put straight Zupreem pellets into the food bowl, and offer fresh vegetables and fruits.  Favorites include broccoli, alfalfa sprouts, bean sprouts, kale, mustard greens, grated carrots, and spinach.  To get Pirko to try new foods, I will sprinkle a little millet on them.  It doesn't take long before he will eat the food without the millet added.
  • Once a week or so, I will chop some vegetables (potatoes, carrots, broccoli, etc.) and put them in a small bowl.  I then crack an egg into the bowl and mix it all together.  I microwave the whole mixture for about a minute and a half, then allow it to cool and break it into chunks to give to Pirko.  I put the left-overs into a Zip-lok baggie and use it another day.
  • Late in the afternoon or early evening, I put a seed mixture into the pellets.  I will stir these together and allow Pirko to go to town. 
  • A time or two a week, I will offer Pirko a two inch piece cut from a millet spray.  I do this only after he has had his other food for the day.  He loves this special treat.
  • I change Pirko's water at least once daily (more often if it becomes soiled).
Cockatiels do best on a varied diet.  Offer lots of different nutritious produce, avoiding avacados and onions.  Other foods to avoid include chocolate and salted or sweetened foods.  Keep pellets available for the birds, and allow foods other than just seeds for their sustenance.

 
The following is a true conversation which took place between Michael and myself.  I am using the version which I posted on the "Tiel Talk" message board.

To access the message board, click here:
"Tiel Talk" by Birds n Ways

Here's The Tale:

Speaking of husbands... I've been debating whether this is okay to add, so if you have any sensitivities to some accidental "slightly off-color" humor, please stop reading now. 

        During a moment of quiet, reflective time together recently, my husband said to me, "I don't know what I'd do without you." I couldn't help it, but my thoughts wandered to my pets, and I laughed, "Oh Heaven forbid anything should happen to me! How would you ever be able to care for all of my animals?" I continued, "Poor Pirko! You wouldn't have any idea how to properly take care of him!" Michael said, "I'd just go onto the internet and find that message board you like so much... Cock Talk." 

        I couldn't help it. I started cracking up and corrected him, "It's TIEL Talk, Honey! TIEL Talk!" 

        Oh my gosh! Could you imagine if he did an internet search for... Eek! *LAUGH*!!!!

 
In the photographs above, Pirko's broken toenail is pictured (the top left of both shots).  Here's what happened:

On October 16th, I came home from grocery shopping to find that Pirko had somehow ripped a toenail on his left foot.  It was bleeding pretty heavily, so I worked on getting the bleeding stopped using flour (I would have preferred cornstarch, but I was out).  I kept an eye on him after getting the bleeding under control, to make sure he was behaving normally.  I could not determine what he could have caught his toenail on to cause such a break.

The next night, I was expecting a houseful of guests.  I was busy preparing for the arrival time when I noticed Pirko had, once again, ripped the nail.  This time the bleeding was even heavier than it had been the first time.  I went into "birdie emergency" mode, trying desperately to get the bleeding under control.  I was also very determined to find the cause of the problem.  After treating Pirko (it was kind of a continual process through the night, even as the guests arrived), I checked his toys.  This time I noticed something I hadn't noticed the evening before.  One of the "apple skewers", which I used to hang Pirko's cuttlebone and fresh vegetables, was broken.  Pirko had apparently chewed off the top decorative bit, leaving a very sharp area exposed.  Pirko loves to play acrobat, crawling all over the bars of his cage and using his toys as jungle gyms and swings.  There was no doubt in my mind that this was the source of the bloody toenail.  I removed it immediately and haven't had a bloody toenail problem since.

Below I have included pictures of the skewers.  After my experience, I would strongly caution against using these types of holders in a cockatiel's cage.  At the very least, I would suggest checking them often for any signs that a tiel has been chewing on them.  As Pirko has proven, broken plastic can be dangerous.
 

 

Above:  On the left (green) is a skewer as it should appear.  To the right of it (pink) is the one off of which Pirko chewed the very top.

Right:  The same two skewers, shown in their entirety.

Left:  Front view of a normal skewer up close.

Above:  Close-up shot of the broken one.