Here's a good link for IDing things LionfishLair.com - Hitchhiker Guide to your Aquarium
Top left. Foraminiferans.
Top right. Could be a encrusting coral. I'm not sure
Center left more Foraminiferans.
Center right coral Skelton with sponge over growth.
Bottom sponge and Foraminiferans.
All good if you see the encrusting one start to open post pics.