Use this nozzle selection guide and choose your orifice size based on the flow (gpm) and pressure (psi) of your washer

Pentair accumulator tank

55 GPM @ 1750 RPM

quick connect outlet or M22

A266 FLEET BRIGHT A50 Aluminum Brightener Acid Size:4 x 4L Box Use this nozzle selection guideFLEET BRIGHT A50 Aluminum Brightener Fleet Wash and Truck Wash Acid. DESCRIPTION: Excellent cleaner and brightener for aluminum trailers or other exterior unpainted aluminum surfaces. Removes oxidation leaving a shining surface. DIRECTIONS: Use in concentrations from 1: 10 to 1: 20 parts with water depending upon the surface to be cleaned and the extent of oxidation. Avoid contact with glass. Can be applied with spray or brush and should be left on