This is an area I know quite well as I frequently treat wells and houses for bacteria in the water lines. The bacteria is very rarely from the well; it usually originates in the house and grows through the lines. As mentioned, standing water is the culprit. In the case of most homes, running out all the garden hoses and letting them run for three days usually flushes out the bacteria and no chlorination is necessary.
In the case of tankage, especially in cases where the bacteria has had time to grow, sterner measures are necessary. If possible, circulation of water through the tank, and water supply system, is highly desirable. The effectiveness of chlorine, and bleach is the most effective form of chlorine, is dependent upon pH. The water solution should be slightly acidic. Most water available will be alkaline or pH neutral. Acidic water is not very common. You can test with a pH strip or just wing it. Before introducing the bleach solution to the tank, adjust the pH of the water to make it slightly acidic. Vinegar, in the proportion of 1 gallon per 100 gallons of water is usually sufficient to do this. Once the vinegar is mixed thoroughly with the water, bleach, at 1 gallon per 100 gallons, can be introduced. Use ordinary bleach with no additives. Do not use swimming pool shock or similar products. Those products are calcium based and will move the pH upwards into the alkaline range and reduce it's effectiveness.
Realize that you may have to treat the tank more than once. this is where circulation becomes important. Ideally, treat the tank and then pump it through all lines, returning to the tank. Recirculate for a few hours, pump to waste, re-treat, and let stand as long as practicable. The longer the contact time the better the results. Circulation, and repeated chlorination, are desirable in bad cases because the nature of the bacteria is that it grows in colonies, one atop another. You may kill the outer colony, and, if too strong a chlorine solution is used, this will inhibit the penetration of the sanitizing solution to colonies beneath. Repeated treatments, in the sanitizing proportion described, are more effective than one shock dosage. Again, circulation is highly desirable.
If your tank has crud, schmutz, or dirt in it; it is important to get that out prior to chlorinating. These will really eat up your sanitizing solution in a hurry, and until removal, may make it impossible to kill the bacteria. One other item, not commonly found on boats, should maybe be mentioned. If you have any "dead end" plumbing it should be removed or opened up and allowed to flush. Pipes that hold standing water, that does not circulate, are havens for bacteria.
I would not be concerned about aluminum or stainless steel in the concentrations mentioned. The chlorine will neutralize itself fairly quickly, and flushing out too soon, losing contact time, is much more of an issue than any potential etching that could possibly occur. This is another reason to not use swimming pool shock and the like. Chlorine in those concentrations is a strong oxidizer.
If you want to be more scientific about it all, you can pick up a hot-tub/pool bottle of tests strips which will test for pH and chlorine. Cheap and easy to use. Furthermore, after completion you can fill your tank, let it sit for a few days, draw a water sample and have your local health dept. test it for coliform bacteria. Test runs about ten bucks and they have special collection bottles. Follow the instructions very carefully as the test is highly sensitive. If you have the slightest bacteria, say on the exterior of the faucet you are drawing from it can result in a positive test, even though the water in your lines may be fine. Or you can do it the "Dutch" way and just drink the water for a few days, and if you don't get the green apple two-step you're probably just fine.
One other method of treatment is highly effective, but may be impractical. Bacteria dies off in hot water. If you can get hot water circulation, above 150 degrees F, through the system you will kill it off. This is more difficult than it may seem. You need to keep the water temp above 150 degrees during the circulation period. In a large tank, it may be difficult to have enough supply of hot water.
Lastly, there is no substitute for circulation. Prolonged flushing will do more than anything else to clean up your system.
“Scientists are people who build the Brooklyn Bridge and then buy it.”
Wm. F. Buckley, Jr.