Ugly Sponge and Possible Tube Worms - OK or remove?

[PotatoPig]

So I turned over a rock in my sump and it has a very ugly sponge on it and what appears to be a bunch of tiny tube worms like creatures - these only show up in the areas heavily shaded from direct light.

Any concerns or mostly harmless?

 

[ISpeakForTheSeas]

Cryptic sponges like that and feather duster worms are harmless/beneficial - in fact, some people purposefully buy cryptic sponges to use as a cryptic refugium in place or in addition to the typical macroalgae refugium.

 

[PotatoPig]

Cryptic sponges like that and feather duster worms are harmless/beneficial - in fact, some people purposefully buy cryptic sponges to use as a cryptic refugium in place or in addition to the typical macroalgae refugium.

Thank you!

This is kinda a “everything in one place” refugium intended to provide a “back of house” area for critter habitat and is full of random feather dusters, tunicates, has a shaded/dark zone below (that I’m assuming is hosting these sponges), with a grow light to get random macros going as well (more as habitat for critters than nutrient control). Seems to work as it’s always teeming with random copepods, amphipods, mysid (mysis?) shrimp, etc that get cycled into the DT by the return pump.