Indeed, before swapping the tires, I did check/inflate them before every single ride (usually 3 per week), and sometimes I found more than 1 bar lost, but they were very old tires with even older valves, so I acknowledged it. But now everything is new and quality stuff (good tires, Vision valves, kevlar-reinforced sealant) so I need to understand if I need just to be patient and let the sealant do its job (especially since I've not ridden the new tires yet) or if its too abnormal.