Pretty simple. Find the corresponding settings for the dos head which is on your dashboard. Add interval, which is the time period of which the dos is running. Modify that interval and Add the ml. And it calculates the dosing based off the set time period.
for example below. My kalk runs from 1230 am to 7 am to minimize ph fluctuation. Also runs from 1 pm to 8 pm for my daytimr growing corals.