I have an exchange Elizabeth that will arrive tomorrow. My tap water tastes delicious here in Sebastopol, CA, but the water hardness is around 120. So, I plan to use the Lelit 35l inline water softener that comes with the machine. There seems to be some conflicting information about how to care for the cartridge. I will get a package of water hardness test strips to test the water, and am wondering how to go about dealing with the cartridge. For example, some places say you should recharge the cartridge with salt every week. Seems like a hassle. Can I just test the water coming out of the machine, and if the hardness is going up, recharge it then? Thoughts here for a low maintenance way to proceed here? I prefer not to buy bottled water, or use some other kind of external filter.