Yup. Look at the Grand Canyon.Do your self a favor and don't fight the water it will always win
African rift lake ones, anyway. I have pretty hard water as well, 16dGH, so I'm setting up a Tanganyika tank for shell-dwellers.Perfect water for cichlids
To add to your point, aside from the money and hassle, there's going to be a time where the pH crashes, spikes or something in between. Gives less room to play with when it comes to the health of the fish. Easier to keep stable what's already there as opposed to bringing in the element of human error.With fish/plant keeping, I've done what I ask of my fish and plants. I ask them to adapt to what they find at times. So I do much the same. I adapt to what I find.
When I find nature testing me, I may go with a try. Like when she sends a few inches of snow, I may try it even though it is more trouble. But when she sends 10-12 inches, I agree to not go!
I treat my fishkeeping much the same. I have to ask which is more important, doing what I want and paying the price or doing what nature is telling me. I find going with moding the water is just more trouble than it is worth. I find all the plants and fish to raise that I want without paying the extra price in dollars or labor. There may be some things that I'm missing out on doing but I've not found those yet.
Why? Most plants do just fine with hard water.If you're serious about growing aquatic plants get an RO system. I would not want to go back. As a note, our water in SE MI is really hard (KH 18-20).