Happy has it. Very hard water with deposits. My water tests at 27 degrees of hardness. I never have to worry about my pH bottoming out as long as I keep up maintenance. I do, however, have to scrape deposits off the tank weekly. We are trying to get rid of all of the air stones because of the deposits that land on the top of the tank. But since we have canisters, we're hesitant. My 55 gal
dosn't have an air stone and it's doing quite well, but I'm nervous about attempting removal on the 150.