Thoughts on what this is???

[JEP1024]

I have a bunch of these growing in the tank. Seems to be a lot more in the sump area and not sure what they are. Sponge of some sort???

 

[vetteguy53081]

I have a bunch of these growing in the tank. Seems to be a lot more in the sump area and not sure what they are. Sponge of some sort???

Image is very dark in blue and best under white lighting but may be spaghetti worm

 

[JEP1024]

more of a white center mass and tiny fibers coming off it