Try looking for polyps. They stick out of the pores of the skeleton and range from about 0.5 to 2mm. You could also look for a skin, but that is a little more difficult. The skin covers the skeleton and give the sps a shiner/slipperier appearence, while the absence of one give a more porous/matted look.
Though anything is possible, healthy white sps' are an extreme rarity in the reef aquaria trade, while bleached white sps' are a dime a dozen. Most likely you have the latter type. If I were you, I would keep the sps in the lower part of the tank (if you have HID lighting ie. MH) with good circulation and see what happens.
[ July 06, 2001: Message edited by: humuhumupukapuka ]
