Ime as long as isnt a thinned skinned species they all tend to out grow most other stony corals outside Pocilloporidae family. Valdia, milie, and tenius are fastest to acclimate to a new system and start growing faster. I probably spelled all of the acro species above wrong too [emoji23]
x2 on ASD Rainbow Millie is the fastest growing Millie I've ever kept.
Other acros in thread all fast. Green Slimer probably overall if you've ever kept track of mass over a year in a healthy system. Valida / Nana fast but still less than half of what a Slimer can put on.