So I think I got some bad advice at the lfs yesterday. I have a 15 gallon tank. 6 neon tetras, 2 guppies and a leopard cory. I went to buy a gravel vac and was talking to the woman who works there. When she asked me about aquarium salt and i told her i'd never used it she was shocked and told me how bad i needed it. While I was there i bought a dward african frog. So i came home, vac'd my gravel, did a 50% water change. conditioned the water, used bio boost, and added salt. Well this morning the frog was dead, and my neon tetras mouths are constantly gasping and are being aggressive toward each other! well 2 of them are bullying the other 4. I need help!