ahhhh....new tank syndrome! looks like my new raceway at the house!
that's mostly diatoms.....but you may hve a little fuzz in there......it ought to go away after a couple weeks, but snails will help to eat it...and cutting back on feeding and light may help to slow it down!
if it's lasting more than a couple weeks, you may need to look into it more closely......but if it just sprung up and seems to be doing better after a week or two, it will likely pass