Ghosts in the tank ?!

All,

Well I have just come away from the tank bewildered by what I have just
seen. I was watching TV and all the sudden lots of white transparent and
opague silk like pieces were floating around in the tank, I can only
describe it to be like pieces of skin in the water.

I have a hermit crab which has been smoking, due to it eating the substrate,
a lionfish, a regal tang and a clown fish. I can only think these weird
pieces of 'skin like' bits have come from the lionfish although there was
none on or around it or failiing that from within the living rock? The tank
is newly matured so aside from these there are no other corals or livestock
in the tank.

Can anyone help me work out what happened?

David