Ceramic as seen in this photo. Sat in sump for a cpl months before transfer. Been as how you see them under the lights with corals growing on them around 3-4 months.While I think about answers to your questions, what qualifies as a fully seasoned tile? What is it made of?
Dont mind how dirty they look thats just how dirty the filters im using makes them appear. They do have coraline growing on them. I can also throw a few shrooms with rubble thats been in system around 2.5 years.