Help with Feeding

Hi. I have a 6 week old rainbow lorikeet which has been hand reared. He has settled in nicely at our home but I seem to be having a problem with it's feeding. All he will eat is the powdered nectar mix (Show Master brand). I have tried offering him every type of fruit, and some cooked vegies (ie sweet corn, broccoli, carrot) but he refuses that and will only eat the dry mix. Is this a problem? Should I persist with offering him other fruits & vegetables too? Your help is much appreciated.

Rachael

P.S Also how can you tell the sex of a rainbow Lori??