Pumps are okay thats all I ever used. Till I found out about Shurflow Pumps
they cut 2 to 3 hours work time vs pump ups.
Most cleaners darken wood....
If for instance you wanted to make a sign out of new redwood but wanted it to looked aged you would put on sodium Metasilicate ( Deck tergent from Super Deck ). Flip that around and you would use oxcialic acid to make the old wood look new.
I did my fir deck last weekend and it looks brandy new again becuase I used oxcialic acid.
oxcialic acid is not bleach and does not burn the fibers of the wood so yes keep using oxcialic acid on new for lite cleaning and old wood after a deck tergent was used.
And get a shurflo pump I have and others posted setup plans in equipment/hardware area here.