I have a 55 gal tank that has been running a long time. I have tried to get guppies and mollies to survive in it and I am NOT having any luck!! My tap water pH tests out at 7.0 but when I do a water change even if it starts out lower with in 24 hrs my tank pH is 7.8 or higher my tester chart only goes to 7.8 but I would say its right at that or 8.0. I cant seem to anything to change that. I have stopped using chemicals because I have now done enough research to know that everyone says pH lowering chemicals are not good! So I am only using salt and stuff to correct the tap water. I have 2 filters in it each for 30-60 gal tanks so it should be getting good filtration. My temp is 79-80. I only feed once every other day now because someone told me that it wasnt necessary to feed every day but that didnt help the pH either. I have read that live bears like that kind of pH however I am not finding that at all. Any babies I am having born are dieing and not because of being eating because I have plenty of hiding for them. I dont understand what is wrong! Can someone help me plz!!!