I just set up a 90 gallon about 6 weeks ago I have gone through my cycle and a brown diatom bloom I am now starting to get the nice green and pink algea. However the other day I started to notice some white specs on my back glass and they kinda looked like grains of sand stuck on the glass, Today I noticed one on my side glass and its actually a spiral shape and it looks kinda like a tube I cleaned it with my magnetic alga pad it took some time but it did come off any Ideas about what these could be. There are about 25-30 of them on the back glass. I dont have a camera so no pictures to show you.