I'm a long time user of the old pool math table, but read that it is no longer being maintained (don't know what maintenance would be required, but anyway...) so I switched to the Android app. I can't figure out how to use it. Are there instructions? I log in, get to the home screen, tap on the Free Chlorine icon, enter my CYA number of 50, Current Free Chlorine of 4, Target Free Chlorine is prepopulated at 3, and the bottom of the screen says to add 2 quarts of bleach to reach my target. I'm supposed to add bleach to drop my chlorine level?