The "Blue xenia" tag can just be ordinary common xenia which under strong lighting also with an actinic can appear as blue.This usually grows fine in most tanks.You should never add iodine to a tank unless you can accurately measure the level first to see if it is defficient.
The name can also refer to a much rarer soft coral which because of it's rarity costs alot more.The correct name for this coral is cespitularia also called blue xenia or african blue coral.This isn't an easy coral to grow and is very fussy with water conditions.It is related to xenia but doesn't pulse.This is what it looks like in my tank under white light.Under actinic it looks like a little neon blue xmas tree.It is also fairly slow growing.
