What is wrong with my fantail Goldfish? It has a light milky string coming from his back end. What is this?

It is probably just its poo but it's not healthy poo, healthy poo should be short and the color of its food. Here is a link that explains the different ways goldfish poop and what each way means, http://www.kokosgoldfish.com/GoldfishPoop.html

Poop

like the other gal said their poop has sort of a casing wrapped around it when it comes out

your fish is healthy and fine

It's called crap or for the faint doo-doo, ca-ca, (etc), The color is probably due to a change in diet or maybe hormonal!

He's pooping :) Sometimes it just hangs there in a loooong string until it falls off.

pooh ! but mines is black!you should only feed it once a day if you feed it too much it could end up floating ontop of the water! erm my fish only had grey pooh oce and when i cut down its food it stopped!

The answer starts with a p and ends with a p.

That substance is not poop. It is goldfish love. You should rub it into your face, it will make your skin appear younger and healthier!

poop u idiot!!! fish crap 2, just like humans

sounds like its poo! lol. have you changed the diet? mine had weird poos when i changed the diet.