[Nords]

TH, you can just let the water conditioner do its mechanical filtration. Add salt if you want to continue Ca/Mg exchange or just let it run without Na regeneration.

Most conditioners have an inlet screen designed to filter out the large flakes (the size of a pinhead). Smaller stuff will gradually block up the spaces in the ion-exchange resin and will be purged when the conditioner backflushes its resin. In other words you can just leave the whole thing alone, stop adding salt to it and ignore it unless you lose all pressure/flow. Then you spend 15 minutes cleaning the inlet screen and repeat the "ignore" procedure.

If you really want to be a nuke about this and you don't already have enough entertainment in the house, then you can install a couple pressure gages on the conditioner's inlet & outlet piping. Clean the inlet screen and backflush the conditioner, then check the pressure drop across the conditioner. You may even be able to compare that number to a design spec if the owner's manual has enough technical info. Then you can watch that pressure drop and clean the inlet screen when the drop has significantly increased. But since your spouse's third trimester will doubtless already jeopardize your life expectancy, I wouldn't do this.