10g water parameters low alk and 6.2 acidic housing 1lgMollie 1jr tank divider w/betta i see fungus velvety skin and gold shimmery on both blk mollies and long stringy poop see thru cottonny spots and film on betta HELP PLEASE STRESSING
What are your ammonia, nitrite and nitrate levels? How long have you had the tank set up? Type of filter? Temperature? Mollies sound like they may have velvet. But it's hard to say anything without knowing much detail and no pics! Long stringy poop. What color?
First thing I'd do is a 50% water change after testing parameters.