I have had my tank for just over 6 months and all has been going well till recently, I first noticed that I could no longer find my frog which has now vanished out of my tank I also found white spot on one of my fish which I am now treating, I also done a 50% water change after finding white fluff all over my plants and now all my fish are just staying at the top of my tank. I have looked on line and followed steps with what to do and it's seems to just be making things worse! Any help will do