Apparently the disk leak detector isn’t rotating backwards enough!!! I don’t know why it would be rotating backwards at all. A leak shouldn’t get better until you fix it. The rate should not go back down until the leak is fixed. I would guess something like a toilet flapper that doesn’t always seat right. A toilet with a 1/4 GPM leak is over 350 gallons per day, or 10,000 per month. A toilet flapper without a leak is 0 GPM and 0 gallons per month.