I dont know but A is all over my rock and B I think it can be zoas but not sure n e more. THe spikey things I want to get rid of but dont know what they are.
i feel like they are preventing my corals from growing. I snapped one off but I noticed as i was approaching it with tweezers something inside the spike moved.
Way too small for a Copperbanded, it will run out food very quickly, not to mention swim space. If hermit crabs are a natural predator I would go them, but very few will pick at them as they are scavengers or opportunistic predators and will not usually go after living animals.