Internal parasite or Just poop

[LunaMax]

so I have a 20 gallon tank with wcmm and just got these guppies which is why might be a parasite but the males don't have this string coming of them from a mom and pops fish store. Most of the females have the string thing. the string is mostly a light pink color to a red I did feed colored flakes which is also I think it might be poop plus it's on the rocks

 

[sgropp311]

It looks like it’s just poop. You should be fine.