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7 months after delivery,  I acid etched my hull, fish boxes and anchor locker.  Put some uhmw strips on the carpeted bunks.
 got some acid in hull, but probably not enough to be very effective,  will pull the floor in a couple years to do inspection and spray then, hopefully no corrosion will be present at that time. 
 Finally to finish, I flooded hull and added a box of baking soda and some dawn dish soap.  Drove up and down a windy hill to slosh it around real good. Boat sure was heavy!
 Thought ought here was to leave a base solution sloshed around to counter any acids present or future, caused from salt or organic matter that find their way in. Planning to use baking soda as a rinse after salt trips.

 you can see the difference in the finish from the anchor guard and the hull after mill finish was removed. 
 
how'd I do?
 
 

Currently being told im an idiot on Facebooks AL boat page....

Looks nice! . . . and you like it, that's the important thing.

Will the oxidation eventually become uniform? 1st trip out the bottom of the hull was a nice dull darker gray, above was pretty spotty and stripy. I guess patience is the order here. Oxidation is good, right?
Lol hoping didn't mean a mistake. Boat costs more then my 1st mortgage!!

Oxidation is what aluminum just does, getting it to look uniform everywhere is a valiant goal that you may (like most of us) eventually decide is not worth the effort. In time the boat will achieve a ruddy grayish patina overall (see my avatar photo) that is easy to live with and will require no maintenance. If cosmetic appearance is important and you don't mind frequent polishing and waxing then gelcoat gets the win.  Mine is about 35 years old, it sports a nice thick crust of oxidation and has looked exactly as shown for the twenty years I've owned it.  I probably washed it three times in the first few years of ownership but I quit after realizing that nothing really sticks to it, it's like one of those teflon coated fry pans 
 
 
 
 

Yeah, I've come to peace with it. It's a boat, not a show car. The ugly protects the beauty,  my kids can polish it when I'm dead and increase the resale to the uneducated.  
 damn it just looks soooo damn good at the bottom of the hull, like someone sprayed with graphite! Dark grey and gorgeous! Give my right eye for the whole hull to look like that!!

Update, acid washed again to remove streaking, and scrubbed with a scotch bright pad in the areas that were streaking the worst. Hull looks very uniform and coloring nicely. 
 transom looks like crap. Lol. So will scrub transom with scotch pad and repeat until it looks as good.

Spark,
usually acid is sprayed onto a hull from the bottom up - so the foam has already lifted scale and contaminants lower down - then when foaming acid above flows down; there are no streaks.  This method seems to be the most reliable in terms of a uniform coloration (whitish or dull silver gray).   If the foam flows downward over un-etched surfaces- that's when the coloration streaks occur, in my experience.

IF you use Scotch Brite (tm) pads to scrub the surfaces while the acid is foaming, that too can help with uniformity but will usually leave abrasive lines in most places after the area is rinsed.   For that reason, buffing the entire area before the acid is done to get a uniform 'swirl' pattern which also helps loosen the mill scale before the acid wash.



Here is an image of a weather helm type cabin that is white metal etched (bottom up) and the fuel tank insert as part of the forward bulkhead of the cabin. The tank has been buffed in a 50" wide drum sander to remove most of the mill scale and leave finish lines horizontally- but at this stage has not been acid etched.  The purpose is to show a white metal etch compared to buffing but not etched metal.  Boat is not etched, at this stage, either.

Cheers,
Kevin Morin
Kenai, AK