used skimmer, coralline?

[Beemo]

i have a skimmer thats been in my closet for about 5 weeks now. it came from my 15g reef tank. i only used it for about a month in that tank before i took it out.
it has some coralline specks on it, pink, green and white spots.
i tried to pick it off, i got some, but theres a little bit left.
now is this coralline dead? or can it populate my "sterile" coralline free new tank? (FO no liverock)

 

[Icefire]

probably dead.