Why won't my abs show even though I have a 6% body fat, I eat healthy and workout very hard?

I get tons of protein mainly from eggs, and I eat lots of fruit mainly apples and bananas....also I workout a crap ton, I do a variety of ab exercises like 300 sit ups, 200 sit ups, bicycle crunch, planks and etc. cardio of running, and I do hula hooping, and play basketball for 2 hours almost everyday....why won't my abs show even after three months of this?