Thanks for the reminder!

I checked the manual, and it says the refill reminders are switched off automatically when water hardness is set to below "5". Mine is set to "7". However, it also says "if you only ever use Tab products in your dishwasher, you can switch off the indicators for both salt and rinse aide".

So apparently the tabs contain both products. My rinse aide still gets used (maybe I should turn it down or off?) and reminds me to refill. Maybe the salt just doesn't get used if the machine senses the water is soft from the salt in the tabs. I could use some of my old supply of Finish Quantum Powerball tabs, which I'm pretty sure don't have salt and see if the salt reminder triggers.

You're misunderstanding the function of the salt. It's not added to the water that fills the dishwasher (the dishes are not washed/rinsed in salty water). Salt in detergent tabs (which I doubt there's any) wouldn't have any effect on softening the water, or recharging the softener mechanism (there's no way for detergent tabs to get into the salt reservoir).

Salt is used to create salt water (brine) to recharge the ion-exchange resin bed in the dishwasher's on-board water softening mechanism. The brine solution is flushed through the the resin bed and immediately down the drain when a recharge occurs ... same as what happens when a whole-house water softener is recharged.

If that's the case (and I agree that I misrepresented how the softening function works), do we have an explanation for why I've gone a year without needing more salt in the reservoir despite having water that theoretically needs softening?

Perhaps, as the user guide says, if there's a specific option to tell the machine that you're using detergent tabs, the water softener operates at a very minimal level with the water hardness set at 7. Have you looked into the salt reservoir to determine if it's empty?

I'll take a look in the reservoir this evening. But I remember when filling it originally that the reservoir seemed to swallow the full box of Miele salt with no difficulty (i.e. not much visible). Not sure the visual test will tell me much. But I could just add more salt now until it becomes just visible in the chamber and monitor from there.

I checked this evening after emptying a load. There was still some visible salt in the reservoir. Not a whole lot relative to how much was initially put in, but at least a cup or so. Must be I just use the salt quite slowly with my water conditions.

My area has naturally very soft water most of the year (under 4 grains/gallon) and it can climb up to about 7 or 8 during short periods of the year, when they need to get water from another source to supplement demand.

So, anyway, my machine is going to be about 10 years old soon, but it was the top of the line back then. I don't have to tell the machine how hard the water is, in fact I can *ask* it how hard was the water last cycle, which is how I know the water hardness varies during the year.

In my case, I have consistently used just about 1 kg (~2.2 pounds) of salt (or one box) per year. About once a year, depending on how much water the city got from which sources, the light comes on asking for more salt. You don't need to add salt, I think, with a cup or so still in the reservoir.

The other difference is that my machine is set for "powder" whether or not I use tablets, because I *want* the machine to soften the water and also use the rinsing agent. If I set it for tablets, particularly for 3-in-1 (instead of 2-in-1), it tends to use a minimal amount of rinse agent, and I prefer the results I get when it's set to powder. Your model is much newer and may use a different programming, I dunno.

In any case, I wouldn't worry unless you are not happy with the results.

Good luck!

I go through salt very slowly.