No, I define the number of pulses for 1m3. This data is theoretical and to be verified.
Adjusted to 300,000 pulses per m3 or 6,000 pulses per 20 liters, I obtain an actual volume of 15 liters. So I had for 6000 pulses a volume of 15 liters.
So if I had waited to have one m3, I would have had 1000 liters / 15 liters = 66.67 * 6000 pulses = 400,000 pulses per m3.
For your second sentence I agree and that is the problem.