ID Please - Cotton Substance

[sharkbite]

My sixth month old tank is growing a cotton like substance on almost everything like mold. I don't know if this is good, bad, normal? After a water change the Nitrate is kinda high. Please help!!

 

[sharkbite]

Here's a PIC

 

[sharkbite]

It's really small and hard to photograph.

 

[stuckinfla]

Is this rock that is being cured? Could be die off, or growing sponge.

 

[clarkiiboi]

Could be at type of sponge. Are they small spots or taking over a rock or spot in your tank?

 

[yosemite sam]

I think I had this same stuff in a 20 gallon tank I used to have. I could never figure out what is was either, but I assumed it was some sort of algae. It seemed to grow on ridges, mostly in darker, or hard to reach spots in the tank. What are your tank parameters? I had somewhat high nitrates in that tank (~30), as I remember, which is why I thought is was algae. I took that tank down a month or so after it appeared, so I never figured out how to get rid of it.