My tank has been showing 7.8ph - 0ppm Ammonia - 0ppm Nitrite and 5ppm Nitrate for the last week and half without change. I noticed today that it now has some kind of funky fungus or something growing on the decorations, plants and on the filter outlet. Also my fish seems to be a bit lethargic the last day or so. Any help is appreciated.
Also hopefully this isn't my issue but do I need carbon filter in my tank? I just realized its been in since it was new about a month and a half ago. Should I change it or just remove it. Thanks.