White Foam - Harmful?

[NavyNano212]

I have no idea what this is...but, my zoo's seem to be dying off around it...Shame too, they were awesome watermelon ones

Any help appreciated...if it is harmful, I will obviously remove it!

If you can zoom in, it might help...

Thanks

 

[rookie07]

Sponge maybe...hard to tell from pic.

 

[tomtoothdoc]

i see a ball shape nub at the end of a tentacle.....ball anemone???

 

[NavyNano212]

Yes, it seems to have tentacles if you zoom in very close...the camera only let me zoom in what you see...
How would an anemone start growing in my tank after 8 years?
It could explain why my zoa's are dying around it...