-thinner whispier first ray on pec fin
-thicker first ray on anal fin
-less pronounced ridge than runs between ventral fins and anus
-if full of eggs tends to swell more on one side of abdo (best viewed from above)
-no breeding tubercles.
-an 'outie' cloaca/anus, kinda roundish...
-In personality I have found to be more antisocial
-gets chased by males.
-thicker first ray on pec fin
-thinner first ray on anal fin
-more pronounced ridge b/n ventrals and anus
-if in season/older than about 3yrs will show white spots on operculum and roughish white spots on the first ray of pectoral fins (feels rough to touch)
-And and 'innie' cloaca/anus -looks more like a slit
-Tend to be more rambunctious, likes to school more, will chase females that are 'on heat'
It can be slightly difficult to tell the difference between a male and female Goldfish. One of the main differences is that during breeding season, males will develop white 'pimples' along the rays of the pectoral fins and also near the gill area. If your Goldfish has these, it's definitely a male. Also, the bellies of females are larger than males, especially if kept with a male Goldfish.
This might help you with your question [link removed] 100% safe
fantail what? guppy, beta, goldfish?