Sponge, fungus or something else among us?

[ReefRoidRage]

Discovered this on my GSP rock after coming back from a business trip. It’s starting to encrust the entire rock/GSP and not 100% clear as to what it is. It does not blown off or come off easily. Any help is appreciated!

 

[Timfish]

Sponge, beneficial and you likely have more elsewhere

 

[EeyoreIsMySpiritAnimal]

Sponge, beneficial and you likely have more elsewhere

Beneficial unless it decides to choke out a coral...
OP, if you can remove the rock from the water, I'd either dip it in H2O2 and/or try to pick off as much of the sponge as you can with tweezers or something similar. While it's true that exposing some sponges to air will kill them, a lot of them can survive so using hydrogen peroxide or manual removal is often necessary if the sponge is in an undesirable location

 

[Timfish]

Beneficial unless it decides to choke out a coral...
OP, if you can remove the rock from the water, I'd either dip it in H2O2 and/or try to pick off as much of the sponge as you can with tweezers or something similar. While it's true that exposing some sponges to air will kill them, a lot of them can survive so using hydrogen peroxide or manual removal is often necessary if the sponge is in an undesirable location

There's only a couple species of sponge which thirve in light that will choke out corals and H2O2 is can be usefull in killing them. I But in 4 decades of reef keeping I have yet to see a cryptic sponge like the one in the OP cause issues. Considering research showing sponges are essential recyclers on reef systems removing DOC detrimental to corals arbitrarily killing them off does not strike me as wise.

 

[vetteguy53081]

Discovered this on my GSP rock after coming back from a business trip. It’s starting to encrust the entire rock/GSP and not 100% clear as to what it is. It does not blown off or come off easily. Any help is appreciated!

This is not sponge but rather a condition known as Chrysophytes which has a cottony appearance which is cellulose and thrives in in low nutrient environments. Raising nitrates and performing a 3-5 day blackout will defeat it. Best removal is to remove rock and place in a container of tank water and scrub off with a firm toothbrush or automotive detail brush and even some 3% peroxide and return to tank while reducing white light intensity.
You can add snails such as chiton, ninja star, astrea as well as pitho crabs to help prevent regrowth.

 

[ReefRoidRage]

I don’t think it’s Chrysophytes, based off your description. My nutrients are on the higher end rather than the lower and my use of intense white light is limited…turned it back on specifically to get the picture.
I do appreciate everyone’s feedback and input. I will keep an eye on it and address it if the issue gets worse, as well as update you all.

 

[EeyoreIsMySpiritAnimal]

There's only a couple species of sponge which thirve in light that will choke out corals and H2O2 is can be usefull in killing them. I But in 4 decades of reef keeping I have yet to see a cryptic sponge like the one in the OP cause issues. Considering research showing sponges are essential recyclers on reef systems removing DOC detrimental to corals arbitrarily killing them off does not strike me as wise.

That's good to know. But I wasn't suggesting "arbitrarily killing them off."
I've had a couple frags over the years that were being bothered by sponges as the sponges grew...maybe there was no malicious intent by the sponges, but I did remove them from those spots so the coral could thrive.

 

[Double monti 61]

Maybe that is a good thing gsp grow like the grass they look like.