I recently added a male tequila sunrise guppy to our aquarium and it was fine the first few days in the tank, now, however, it looks as if there fecal matter hanging out of the bottomof it and I am not sure if it is intestines or fecal matter.I think it is dying from something but I am not sure of the cause, it is the second fish that has had problems in our tank.Any insight to this may help.
there might have been aa virus in the tank already. so i would just filter the water and treat it. if he dies. keep cleaning and take some of the water to an aquarium to be tested
it really sounds like poop.
if he swims around and eats its nothing, just poop.