yellow sponge

Good afternoon all :) I'm going to do a rescape on my tank because I'm not happy with it and I want more open space between the rocks and more open area's on the sand bed. I am putting a plan together but there is something that worries me a bit.. There are a few rocks that are covered in yellow...

I recently picked up a couple live rocks with yellow sponges. They came out of the seller's sump. I put them in to my DT, but now the sponge is turning grey. I think this has to do with flow. They are in shaded spots with less flow. Should I take them out an put them in my sump, or let...

Hey guys, I picked up two sponges 2 weeks ago - A red finger and a yellow ball. Both have been doing well and both were completely submerged when added to the DT. 2 days ago, in the morning, I noticed some “white” fuzzies on the red finger and today in the evening, it seems to have...