Good questions and I'm curious on the actual science too. We're using liquid pool chlorine diluted with water -- pool chlorine is just higher-concentration ble

Good questions and I'm curious on the actual science too. We're using liquid pool chlorine diluted with water -- pool chlorine is just higher-concentration bleach. Although not scientific by any stretch, I know that the general guidance (and my experience from chlorinating & testing pools) is that you want to check the dates on the chlorine when purchasing because the strength can be substantially lower than stated if it's been sitting on the shelf for a long time. My understanding is that the effect is worse if the product has been sitting outside in direct sunlight / high heat (ie outdoors at a home improvement store), which I believe causes concentration to drop faster. If you're having trouble finding bleach though, likely can get some at a pool store or a big-box home improvement store in the pool chemicals area. We just mix it down to suitably diluted concentrations in a spray bottle -- readily available & much cheaper than off-the-shelf spray products. I wasn't aware it might be 50% lower concentration in 30-days though, will have to re-mix ours here soon. But that's still small potatoes overall, a gallon of bleach goes a long way and has lots of uses. :)