1)don't use bleach
2)being the deck was built one year ago i'm imangining it has never been cleaned
3)first time cleaning on cedar is tough, because the mill glaze must be removed
4) when the mill glaze is removed the first time you must use a mild detergant such as armor all ez deck wash mixed 1:1.
5) once the deck is sprayed down, keeping a hose ready as not to let the chemical dry, mist it with the water intermittently (is that spelled right?)
6) as you power wash with even strokes from one end of the board to another you will see what lookes 1/64" of an inch of wood sheeting off' (this is your mill glaze)
7) now when your deck dries there will be no stain, there will be no bleached out cedar. But ever so slightly you will see near the knots a peach fuzz.
8) with a rotating palm sander have a day laborer go over every inch of your deck (depending on the size of your deck 1-2 days) new york day laborer 100 a day plus lunch
9) your deck is now able to absorb stain because the mill glage is gone.
10) because cedar is such a soft wood, i recommend using super deck deck stain maybe the color natural natural the first time.
11) every 2-3 years there after a light cleaning with armor all ez deck wash mixed 1:3 then one coat EASY!
12) if done as stated above you will smile ear to ear
13) in new york i would charge $1500 for a 20x20 deck plus 200 for the day laborer