White stuff on my sandbed 3 month old tank

[KingAh123]

Look like mini fish

actually does xD

 

[vetteguy53081]

Ya better pic... I'm still wondering if pineapple sponge, it has somewhat that type shape to my eyes, and at 3 month mark would make sense.
I'd be curious to see it once siphoned out under more magnification.

Pineapple sponge does feed off silicates but often found in shady areas such as under rock or sump or overflows.