recess62 said: The only thing you can do with the apex is control power to the tunze i.e. Turn it on or off. You cannot use the apex to control when the unit adds water to the sump. That being said you can program the apex to turn off the tunze under various circumstances. More @Wikipedia
Hover over any link to get a description of the article. Please note that search keywords are sometimes hidden within the full article and don't appear in the description or title.