Recently bought a new 15 gallon tank set up. So I made the mistake of not cycling the tank..... I know I'm stupid. So the old lady put fish in it and I'm stuck thinking about what to do ! A few fish are dying. My tank levels are all zero soooo don't get why they are dying. Added that bacteria in a bottle Need help anyone have imput ?? Like using an old filter from my tank to help keep things under control ??