I noticed this evening, this strange fur like things next to one of my bubble tip anemones. Not exactly sure what it is, or whether it should be removed.
From 1,40 -2.00 minute mark ,I got some similar but blue,usually sponges like shaded areas of the tank so under corals, under hangs on Rocks etc.
I'm thinking these blue tubular things are sponges anyway,looks like one sponge growing over another like " rotting food ,mold would " camt think better way to describe it sorry ,but yours got same