adelaide

i have a desert tortoise...it is about 2 years old and it's on a diet of Rep-Cal Tortoise Food and romaine lettuce. i have tried to get it to eat other things like grated apples, carrots, celery...but the only things he'll eat is his current diet and some avocado. i've read that the romaine and avocado aren't such great nutritional items...is the Rep-Cal Tortoise Food enough? please help!? what else can i give him?