do zoas only grow up toward light?

[loyalty]

i'm looking at some older frags, and almost all across the board, my colonies start at the frag and grow up the rockwork. in fact, the frags i put in flat areas have yielded the least growth. is this a universal thing? TIA

 

[AIMFish]

I've read that they seem to grow better in areas with higher flow. I'm interested to see what the veterans say

 

[IanInDC]

I've been curious about this too. Interestingly enough I seem to get the best growth along the bottom of my tank, where the zoas are flat and parallel to the light, rather than encrusting up some branch... could also be a flow thing though.