Start with half the maintenance dose indicated on the bottle and observe how the skimmer reacts (so you can adjust it to be a little drier, either by increasing the height or using the drain, if there's over-skimming). Not all aquarium systems are the same and they can react moderately to very strongly to a normal dose of skimming solution. You can literally see the product working. By gradually increasing the dose, you can more or less control the skimming capacity. Note that these parts (highlighted in yellow) of the skimmer must be cleaned weekly.
During the first week, add this daily (for the first 5 days). From the second week onwards, add it once a week until the bottle is empty. For new systems: 5 ml/40 L per day for the first 2 weeks; for established systems: 5 ml/100 L per week.
