Cloudy white tube looking critters....

in parts of my tank. They're pretty much around the filter intake and on some fake coral. Does anyone know what these things are and how to get rid of them if they're bad for the tank?
Pic:


Thanks.

EDIT:
75g FO tank 9 months old.
All water tests are normal
Water Temp is 80 degrees.
5 gal. water change weekly.