Any idea is it a flatworn?

[Gennaio]

Take a look amy idea what this is?

Found a couple. I feel like its a worm but its just there drifting.

 

[HOOPDEEZ]

Doesn’t look like a flat worm. Can’t make an id with those pics though

 

[Gennaio]

Thinking posdibly somekind sponge too

 

[ReeferWarrant]

Photo is pretty blurry, but yeah I doubt it's a flatworm. Is it moving much or staying in that one spot? Try using a turkey baster or something to push some water across it, or isolate it in case it is something bad.

 

[Gennaio]

Itsthere drifting in the fliw but its attached to the rock

 

[Gennaio]

Ok all you reefers check these pics out. Again warning it is very hard to photograph as the critter is translucent.

But....

This morning when kights still out i saw it and it expanded to over 6 inches. Still attached to the rock and drifting in the current.

Prior not even an inch.

The video you can see it little easier.

Any ideas on this?