Help in creating a flow

Recently purchased a Homewizard water meter for an analog water meter. In addition to the Homewizard app, I also installed the Power by the Hour app. What I want to achieve now is the following.
I want to create a flow that shows how many liters of water were used each time water is tapped. I then have this displayed via the Cast a text to google app. Now I have almost tried all combinations, but besides stating my total water consumption or the number of cubic meters per hour, day week, etc… I fail to get the report of the consumption in liters. I realize that this cannot be achieved in one flow, but with advanced flows this should work, but I have no idea how. Are there any of you who have such a water meter and use it in the way I would like. All ideas and suggestions are welcome.