Hi all!!! Very new to reef and saltwater aquariums. We’ve had our pico tank for a few weeks now. We’ve noticed a growth of white stuff on one of our live rocks and we are having a hard time identifying it. It seems stiff (it’s not moving around in the water, and it doesn’t really move when a crab walks along it). Please help! We want to make sure it is harmless :). Thank you!!!!
