Hello aluminumwelder,
I am kind of new to anodising, but have done some. I would be very wary of having 200 gallons of H2SO4 in a single tank, unless you are a "Cleaner" for the mafia ;D
for the long pieces I would try a plastic channel similar to a rain gutter or pvc pipe with it's top opened, cathode could be Aluminum flashing used as a liner, lead probably better, but expensive.
You could mask off the areas you do not want anodized, with tape maybe kapton tape, maybe plastic tape. Temp control is another matter, ice bottles, or Titanium tube circulating ice cold water . . .
93% x 55 gallon is going to make a whole "shed load" of electrolyte
Remember to use every safety method and PPE available including shower and eye wash stations, much cheaper than injuries.
You want a constant current rectifier, of the appropriate size, secondary containment vessels to catch spills . . . check out Caswell Plating for more information their low current low acid concentration seems to work. . .
The grade of aluminum will affect the difficulty of anodizing and the "scratch ability" of your work, and my last point is , Have you considered powder coating your finished frames? It's safer, very good looking, does not give your welders trouble, (because it's applied after) and very durable, and it is something you could do,in house, given some hot lights . . .
We're not in business to make parts, we're in business to make money, making parts is just how we do that.