I have been using just dichlor but the more reading , I'd like to switch to bleach after the cya builds up. My tub is 449 U.S. Gallons . I have it down where , upon fill up, I adjust the TA and PH , then throw in a quarter cap of dichlor to kick start it . I'm also using 5 oz of aqua fitness a week. So , by adding a 1/2 teaspoon of dichlor a day , my tub maintains 1-3 ppm at all times . If I have a guest with me , I give it a extra half teaspoon for them . I usually shower before I get in since I'm a painter/ drywaller . So my question , by being consistent with the 1/2 teaspoon per day, is there any way to know when I hit my cya amount where I can switch to bleach ? 2nd question, how much " chlorax ultra" ( Canadian) would I use to equal the amount of a 1/2 teaspoon of dichlor. Unfortunately , I don't have a Taylor rest kit . Just strips . My water is always crystal clear .