Question Mystery Item

[paulywg]

I have been seeing a few pockets of what looks like cotton showing up in crevices can anyone tell me what they could be.

 

[uberlink]

Could easily be sponge. See if it continues to grow and develop a stalk-like appearance with the occasional swiss-cheese like hole. If so, likely a type of sponge. No big deal.

 

[sk8shorty01]

I would say they are Q-tip sponges. They are a good thing, and also a good sign that your tank has good water quality. You can do a google search on them and see if that is in fact what you have, but I would say I am almost positive by your description.