Good.

The fact that you have a DE filter with a slide valve means vacuuming to waste would be difficult -- you'd have to add some valves. That makes it impractical to use the whole pool lime-softening technique, at least for now. But there may be some intermediate steps you can follow.

One point I should emphasize is that the so-called BBB method I originated (I came up with the method, not the name) is not literally bleach / borax / baking soda: rather those products are more symbolic of the approach of using the easiest, cheapest and best way to care for your pool. And one of the fundamental points of the BBB method is that you have a POOL, not a 'set of test numbers'. So, we don't worry too much about numbers, when they aren't causing a problem.

Unlike pool stores, who want to sell chemicals, we try to avoid fixing what's not broken!

In your case, if you have no tile-line scale . . . you are NOT having a calcium problem, even if your level IS 560 ppm. So, let's get more accurate info on your numbers, raise the chlorine, and then re-assess.