Zoa pox - white spots inside or outside on stalk?

[Mightyfish]

Could anyone please tell me whether the white spots are appeared on the outside of stalks or inside? I googled photos but they are a bit confusing. Once it is infected would zoa eventually shrink in size and then melt away?

 

[Mightyfish]

The polyps in question is the bottom one of the three. It appears to have one white spot. Is it pox?

 

[Jone]

http://www.zoaid.com/articles004.php
a good place to start,,time is of the essance..