I agree with those who feel the acid wash does take a bit of aluminum with it.
Up until I put in the vertical lift last year I used to winter store the tritoon on the trailer.
Each year I would power wash the tunes, outside was easy but under the boat on the inside
of the outer 'toons and both sides of the center 'toon required crawling on the gravel driveway
and trying to power spray the center one. Too much, too wet, too old for that.
However, if you are going to do that, instead of acid wash try using a gallon of so of white
vinegar in a spray bottle to soften the build up. Leave it on for an hour or so and apply
a second coat. The power washer can now get the softened algae off a lot easier.
P.S. Once you have it really clean, buy a lift to use during season. Then store it on the
trailer or store it on the lift. It makes boating a lot easier and winter maintenance goes much smoother.
Captain Tony
2005 Summit by Triton - 220T Platinum 3Log
2005 115HP Mercury Optimax - 228 Marine Master Trailer
St. Louis & Lake of the Ozarks, MO.