The trichlor tabs will be okay for the week that you're gone--just test your pH (you need to do that anyway since you've been using dichlor, which is also very acidic) and push it up to the 7.6-7.8 range before you leave, so that the trichlor won't push it down too far. It's okay to use the cal-hypo if your calcium hardness levels aren't too high--if they're less than 200 or so, then they should be fine to use.