My water is also liquid rock. Straight from the tap, it reads 8.4ph, 300ppm KH, and 300ppm GH. I really don’t know if that is a true KH or GH reading as that’s the upper limit on my test strips. Despite the high readings I am getting decent to good growth from my plants with what I guess most would call a low tech setup. No fish currently, but as I’d like to get some tetras with a ram (blue or Bolivian) or Apistogramma as a centerpiece, the water conditions are far from ideal. I did some experimenting with different dilutions and at 75% distilled/25% tap I’m getting readings of 6.8pH, 60ppm KH, and 75 ppm GH. As I only have a single 20 gallon aquarium, buying distilled or ro water for weekly water changes wouldn’t be too costly for me. With just plants and snails, would it be an awful idea to remove 75% of my water and replace with distilled or should I do it slowly over a few water changes? Years ago I had multiple aquariums with several different tetra species as well as rams. I never really tested my water parameters back then but I assume they were close to what I have now as most water around here is the same. So I’m not really even sure if I should mess with it at all. Thoughts?