Thanks Larry, that makes me feel better to hear someone claim to use such a small amount. I was beginning to think I was going crazy, everyone using such a large dose. I understand what most articles are referring to, dosing high enough to shock the system and kill bacteria in the tank and lines, then flush it out. But its hard to find established information for ongoing treatment of an in-use system without using very expensive equipment. I still haven't had the time or resources to set up my system the way I would like. Eventually I will get where I would like to be and have all of this equipment in place. But for the time being, bleach is going to have to do. And very small amounts at that. I'll try a 1/4 cup with the next tank fill.
Do you test your water for its chlorine content? If so, how and what is the reading? Once I get my dosage correct, I would like to be able to maintain the system regularly. In other words, not have to run the tank all the way down, and refill completely to know to add a specific amount of chlorine. If I could test the water (lets say with the little swimming pool test strips, for example), then I could top the tank off when it was only half way down, test the water when full, and add enough chlorine back in to get it back to specs. After all, the purpose of the tank is to have a reserve in case my well were to run dry. It would be unfortunate for that to happen right at the same time that my tank ran dry also!