Looks, like the sun coral people are subscribed on this thread.
I have some questions:
1. Is this Tubastrea aurea?
2. Was Tubastrea aurea reclassified in Dendrophyllia something? Can't find the link right now.
3. Septal pattern differences within Tubastrea - maybe you have a photos or additional information.
In Dendrophyllia, the calyces follow the Pourtales Plan wherein the septa fuse in groups of three together at the center of the calyx. Tubastrea conversely shows no central fusion of the septa.
link . More drawings of Pourtales plan and skeleton photos are
here , only no translation available.
My orange tubastrea's skeleton, possibly T. faulkneri (pink-salmon shade at arrival and new colonies have it):
4. What do you use for improving coloration, other, than cyclop eeze and white fish (the fish is an ultimatereef.net non-photosynthetic forum information)?
5. Who has/had dedicated NPC tanks with tubastrea - how high flow was tolerated?
I have suspicion, that scleronephthya and tubastrea could be incompatible because of flow.
Any particular tips on filtration?
I would like to remove my sun corals from the big tank and keep the fish in clean water - they deserve that.
6. Who has sun spawned and new colonies growing:
what to do with them and how? I would like to remove them from main tank and grow in easily accessible for a tweezers feeding place, but that would require removing all the big rocks - they are plagued by babies.
How make a compact placement of the babies, with room for a growth?
I know, that one of the options is having a sun coral forest

, as Daniela has (
13 Mb pdf link), but my skimmer (ASM G-3, venturi, needlewheel pump) can't handle that. Could do that at nano-scale (10-12g tank with 7x oversized skimmer).
Will appreciate the input and, especially, the photos.