Myka
Reefing since '93
The growth on mine is thicker than when i bought it due to the slow growth where the tips thicken slowly rather than extend in the classic shooting tip look. If you look at the last pic from front on you can see the tips starting to 'shoot' and as such they are thinner than back further into the colony where the original tips have been pretty much sitting blue and stagnant for many months.
These tips are the same diameter as the ones you see on the original piece and if you look closely you can see a violet tinge rather than pure blue on the new tips, i think the entire thing will return to a violet blue color when all the visible tips are growing. I think it's so crazy blue because it's been stagnant.
Yeah, I see this in Bali Aquaculture colonies a lot. The new growth looks nothing like the "wild" growth. It can make it awfully difficult to ID what the species may be! I'va also seen the same thing in regards to color - they get super color saturated in their "old" growth, and the new growth is significantly lighter. However, this makes a nice contrast in larger colonies when there is a darker base an lighter growth tips. Besides, every Acroholic knows white growth tips means you can grow an Acro like nobody's business.
I have a nasuta with those sweet dark purple/blue polyps too - I'm not sure what it's doing in my tank yet, it's been stagnant for a long time, but I'm seeing a couple of growth tips popping up at the base in the last few weeks.