Some of the crying could be searching for his clutch mates.
First, weigh him (on an empty crop - so first thing in the morning). Then feed 10% of his body weight per feed. You can go a little over, but don´t feed until the crops are really full or you could risk stretching it. It is always best to feed a little less than too much. When the crop still has food in but is almost empty, it´s time for another feed.
At night time, let the crop completely empty, and then weigh him before feeding so you know how much food to feed throughout the day (this will change slightly everyday as the bird grows, you can feed a bit more).
Be sure that you are preparing the food as per package instructions, using a thermometer to get an accurate reading on the temperature. It´s important the formula isn´t too thick or thin as that could contribute to the hunger.
As for the single baby scenario, he needs a ¨sibling¨. A very small soft toy that is the same size as your bird, with no loose threads or buttons, glitter or sequins is a good item. If you can´t find something like that, a clean sockrolled up into a tight ball to make a ¨buddy¨ the same size as your bird will do. Place it in the corner of the brooder for your bird to snuggle with, place him next to it when you return him to the brooder after feeds.
On of the most common causes of crop problems is incorrect feeding and housing.
Feeding is the easy part, follow package instructions, use a thermometer, be sure no lumps. Don´t over feed.
As for the housing, where do you live? If you live in a colder place, I feel this is just not a great set up. If it´s hot and humid where you are, you can get away with a little box lined with bedding, but for anywhere dry or cold, you will need to set up a brooder. You can do that by using a critter carrier, lining it with a couple of inches of aspen shavings. Place a digital thermometer/hygrometer inside so you can monitor. Use the elec blanket under one end of the critter carrier to get it warm, checking the thermometer to be sure it doesn´t get too hot. You want the temperature to be consistent. instability will very likely cause crop problems. If the humidity reading is too low, you can place a dampened paper towel (kitchen paper, or a cloth) on a little plate in the opposite corner to where the ¨chicks¨ are.
Never put open water sources inside.
Once all of his feathers have grown and been preened open. This is when a bird can regulate their own body temp and can go and live in a cage rather than a brooder.
Here is a handy thread to save/bookmark. There´s a grid you can either print or just copy using a pen and paper to log the birds weights, formula feeds, times etc.
With these Links-I hope to bring You as Much information as I can to help anyone that finds them selves having to Hand feed A chick Lots of tips for Breeders-with links for Hand feeding etc http://www.parrotscanada.com/breeder...rbreeders.html A new way to Hand feed-With a Cup...
forums.avianavenue.com
Post any questions you have! Better to ask about stuff you´re unsure on.