I've used the generic Sun brand oxy-clean. I mixed 2 scoops oxy cleaner with 2 cap fulls of generic color safe liquid bleach per gallon of water. Sprayed on with a garden sprayer. Used about 1000psi and a green tip. Worked really good! Didn't show any wood fibers like Armor All (bleach based) deck cleaner did.
One deck was really old and grey. I never thought I'd get it clean. Looked almost new when I was done. Customer even gave me a $20 tip he was so happy!
It didn't work very well on vinyl or brick, but it sure brightened up pressure treated wood.
I tried that sun brand stuff today too and was pretty happy. I mixed about 1/4 of a tub (small tub, 2# i think) with 2 gallons of water. Sprayed it on let it sit a few minutes. Had to do some scrubbing but its cleaned it up alot.
On some spots I applied the powder directly to the wood after I had scrubbed it the first time. Then I scrubbed again. Got it alot cleaner. Washed with 40 degree size 8 tip, which gives 1000 psi also. This deck (mine) was nasty. (very grey and black) still dark, but not like it was. Atleast you can see the wood now.
It will probably take several applications/ to get it totally clean. I also need to get a different brush.
What is used to brighten wood? The oxy clean cleans it, but i think it could use to be brightened up too. Maybe the wood is just too old? I dont know. Doesnt look to be in the best of shape. Still looks alot better, tho!