I have a 55gal tank that has been fishless for about 2 months. I kept the filters going the whole time and now we have added barbs and loches to try and get things going again. I'm having trouble getting the pH under control. It is exremely basic & I can't get it down-the amount of "pH lower" chemicals I've used is starting to worry me. I have exchanged water twice & cleaned the tank & gravel. My tap water is basic also. Do I need to completely empty the tank and clean everything and start over as if a new tank? Or what? Will plants or air bubbling help?