Is this a Algae?

[RYcube2951]

My rear filter compartments in my Biocube29 have a growth that look like pieces of rice and attach to the walls and glass. I use to have a CPR3 skimmer and a lot of this growth was on the inside of the skimmer body. I can scrape it off and siphon it out but was wondering if anyone knows what it is. It shows up as yellow in the photo due to the flashlight. The organism is actually white or opaque in color.

 

[JGT]

Pics aren’t great but probably pineapple sponges based on description. Harmless.

 

[RYcube2951]

They are pretty much the size of a grain of rice and do not seem to get any bigger.They are only in the rear filter sections. I have had the tank running on 4 years now.

 

[RYcube2951]

I think my description of their color is wrong. When I got rid of my old CPR3 skimmer I cleaned these out of the inside chamber. They were more like oatmeal in color.

 

[JGT]

I think my description of their color is wrong. When I got rid of my old CPR3 skimmer I cleaned these out of the inside chamber. They were more like oatmeal in color.

Sticking with pineapple sponges. Typically populate skimmers and sumps.