Vibrant will not kill your SPS or any other coral for that matter. Follow the recommended dosage and you good to go. Also, don't get discouraged if after 2 doses the bubble algae is still their. it took me 6-7 weeks to visually see the bubble algae wilt away.
I have not had this issue but would like to bring it up is that a fair amount of reefers have said that it did wipe out their macro algae and they suggest to remove it from the system. I did not remove mine in both of my systems, and my chaeto did not die.
There is also a huge thread on this forum that you can search for and see other experiences with it