Algae that has tubes

[Jason_Mack]

I noticed recently a lot of fuzzy algae in my tank. It has overtaken the underside of my shelf and made its way into my refuge. Also, there are these hard white spots on my tank walls that I can't figure out. I am relatively new to reefing (October of 2020). Any help would be appreciated because it is making my tank look really bad. I have a 75 gallon tank, Curve 5 skimmer, Pentair UV 40 watt light, (2) hydra 52's and I perform daily glass cleaning and weekly (10) gallon water changes. My Alk is 8.0, Phos. 0.15, Calcium 496, Salinity 1.027, temp 77.2 degree's, (measurement taken with Hanna testers). I have a fairly stocked tank with 13 fish (2 are tangs), 3 shrimp, 3 crabs and a few snails. Please help me figure out what this is and how to get rid of it. Thank you so much!!!

 

[Gtinnel]

I cant help with the algea but the white dots on the glass are probably spirorbid worms, and if so are harmless.

 

[NeonRabbit221B]

Pinnapple sponges?

Can you circle what you are inquiring about because there is about 10-20 different organisms in this picture.

 

[Jason_Mack]

I circled one, but there are hundreds of them under my shelf.