Feather Dusters?

I have very small spots on my aquarium walls, (also have some coralline algae) I cleaned the front yesterday with my magnet cleaner and today I have more than 100 of these little spots back on the front glass with the little copepods too. These little spots look like very tiny feather dusters, is this what they are? I'm very new to salt, and not sure if I can get a clear photo of them cause there so small. I clean them off and there right back, minutes sometimes, later. I'm not worried just curious what a spawn of them would look like. Also what does gorgonian look like, I have what I thought was a plant but on the end of the twigs are little round dusters mounted on a pivot and move around with the current direction...hope this is where this question should be posted, new here. Thanks

 

I am going to guess tiny looking creatures that look like feather dusters are hydroids. Do they have a tube? Are they flush with the glass? Are they white or opaque?

 

Things on the glass have no tube and are flat, opaque...with dark edge.

 

If they are curly i vote feather dusters.
Most salt tanks go through a phase where you have a galzillion of them in my experience. No worries if that is what they are.