Did this sponge die?

So almost over night these things showed up in my tank and then a few days later they are all turning black. Are they dead? Do they need to be removed?
Thanks in advance for any help.

When it showed up


A few days later

Yes, that appears to be tissue necrosis. It will foul your tank, so I would keep an eye on it. I would remove as much of the dying material as possible and run carbon...and do a water change. Keep an eye on your ammonia and nitrite.

I'm sure the sponges will grow back in time. It doesn't take much to restart a colony.

Aloha Preston,

I completely disagree. Sponge changes color and that Sponge is not dieing. It looks completely healthy. It could also be another Sponge growing in and infiltrating over the first Sponge.

Dead sponge does not have that solidity and shine to it. I would be cautious about removing it from the water to take the pic. I definitely would not remove it from the tank. Sponge likes being in the water and removing it can trap air which disturbs its water circulation system. That water water movement system through small channels and capillaries is how it eats and excretes. Sponge does not wound, get infected and kill our entire tank. If it does die, it typically decomposes without causing any trouble, leaving a silicate structure as a legacy of it's existence. You have a good thing going there. Leave it alone and it will help your tank be awesome.

Gee whiz folks, I have to say that I have noticed a tendency these days to consider every unknown thing as some kind of problem. Yes, there are problems, but our tanks are little environments that, if left alone, can take care of things. We need to trust that life is able to work things out. Yes, there are pests and diseases, but we know what to do to control the pests and we are learning more and more about the diseases, but in the meantime, let's trust in our tanks ability to grow and correct it's own problems.
Sorry, I just had to get up on my soapbox for a moment here.

Mahalo,
Mark
808-345-1049 call or text anytime to "talk reef"

Thank you everyone for all the help. You seem to be very knowledgeable with all of this Mark.
The second picture was from last night and I have an update picture that I just took when I got home from work today. Please let me know if all your advice still stands. I am pretty sure that my purple dottyback is eating it now.

I stand humbly corrected i guess all is well. I guess even a decade of reefceeping won't give you all the answers hahaha. I'm sorry to go off topic a bit, but Mark that is a fantastic sponge, is it in one of your tanks?

Green Sponge in my tank? I wish. No, that was a pic I found long ago. I use it for occasions like this.