It can be difficult to tell the gender of a young goldfish most goldfish will start showing signs of their gender by the time they reach about 3 or 4 months of age, and should be easily identifiable once they reach about one year of age.Īnyway, I hope someone finds this useful. Peas act as a laxative to goldfish, and will help her expel the decomposing eggs. If you suspect that your female goldfish is having this problem (called eggbinding), stop feeding regular food and feed her exclusively shelled frozen peas for two to three days. Females that don't expel eggs are more prone to infections, because the eggs typically begin to decompose before they leave the digestive system, and buildup of gasses can cause pain and bloating, and in severe cases, septicemia and death. Some females prefer to use a bubble wand or airstone to aid in expelling eggs, but females that don't expel eggs will reabsorb them and they will come out in squiggly white poops. Females can expel eggs without a male present, but neither of my two females have done so in the two years that I've had them. They also generally have rounder pectoral fins, and have a convex or "outie" vent. A male will generally have a concave or "innie" vent.įemale goldfish: Female goldfish are typically rounder than males (although again, it can vary with age, nutrition, and genetics). You can also tell by the shape of the pectoral fins (males will have more pointed pectoral fins), and by the shape of the vent (anus). Sometimes 3 males or you put group of them like 5 males and 23. The number and placement of breeding stars will vary, but almost all males will develop them at least once in their lifetime. You will need 2 male Goldfish and 1 female Goldfish. Male goldfish: Male goldfish are typically slimmer than females (although this can vary with age, nutrition, and genetics) and will periodically develop tubercles generally referred to as "breeding stars" on their gill covers and pectoral fins. This is a question that I get asked pretty often, so I figured I'd post this on here in case any Redditors were wondering.