Great white sharks. Trophic Pyramid Information that is in video: An ecological pyramid (also trophic pyramid, energy pyramid, or sometimes food pyramid) is a graphical representation designed to show the biomass or biomass productivity at each trophic level in a given ecosystem.
The risk is that you may not be able to remove all the acid and if it is left on the metal it will continue to corrode the metal. So to give you a quick answer, you can use vinegar to etch the aluminum, but you have to rinse the surface thoroughly to remove all the acid residue.
Use white vinegar. The vinegar reacts with the rust to dissolve it off of the metal. To use, soak the metal in white vinegar for a few hours and then scrub the rusty paste off. If the object is too big to soak directly in the white vinegar, pour a layer over the top and allow it time to set.