I've got a quick question regarding my GH, which as the subject states is testing at 25dGH which to me seems awfully high. My KH is at at a decent 7dKH, so I'm not to worried about that. But as for the GH, what effects does this high of a level have on plants, if any? What about fish like tetras that supposedly prefer soft water? Will a water softener pillow work for this and is it cost effective/worth the trouble? Any side effects?