So far my pool has been pretty even-steven CH-wise.
@JC707, you might consider plumbing the way I did. I replumbed my auto-filler to my softener, but I also maintained the original connection to the city water. I've been running it 100% soft water since doing that, but I left the hard water connection in place so I could switch back easily, with the twist of a couple valves. I did that in case I ever wanted to add CH to the pool. It'd take a while, but it's free and effortless.
The other reason I did that: my softener is on my house's interior loop, so when I turn off the water main to the house, the softener goes down, too. My hard water connection is plumbed to the exterior irrigation loop, which branches off before the house main, so it stays on even when the house is shut off. I once had a pipe burst while on an extended vacation, which destroyed my entire home. So I now turn off my house main while away. Which means my auto-filler would be off, and that can't be so during the summer. So I turn off the house and switch the pool over to city water while away. House interior is safe but pool and garden still get water.
Here's how I did it, if you're interested:
#76