Hi and welcome to TRT!
i moved yourthread to the general area for you.
the smaller white area look like "qtips" to me , can you get a closer shot of them?
now the second shot of the same area shows the star of white encrusted sponge. that is a major headacke.. that that piece out and scrub it off!!! leave the piece out of the tank and let it dry out. Air is one of the killer for sponge. Do not scrub it in the tank. any piece of sponge no matter how small will start a whole new area of growing... it took me over 6 months to get everythingout of my tank.. everytime i though i hadit gone , i ended up finding an area that i did not see before...
So what are your ideas for the tank?
need something to read? just ask me.