Can SPS have dual polyp color?

[Snappy]

My book doesn't even have Acropora tumida listed. I think its time to order me some more books! Would a full-colony shot help for better identification?

Yes that would help and for a good coral book I recommend "Corals of the World" by J.E.N. Veron Vol 1-3
Here is a link for A tumida although once I see a full colony shot my id prognosis may change
http://www2.aims.gov.au/coralsearch/...0pages/558.htm